Risks associated with the transfer of toxic organo-metallic mercury from soils into the terrestrial feed chain

Although the transfer of organo-metallic mercury (OrgHg) in aquatic food webs has long been studied, it has only been recently recognized that there is also accumulation in terrestrial systems. There is still however little information about the exposure of grazing animals to OrgHg from soils and feed as well as on risks of exposure to animal and humans.In this study we collected 78 soil samples and 40 plant samples (Lolium perenne and Brassica juncea) from agricultural fields near a contaminated industrial area and evaluated the soil-to-plant transfer of Hg as well as subsequent trophic transfer. Inorganic Hg (IHg) concentrations ranged from 0.080 to 210 mg kg^− 1 d.w. in soils, from 0.010 to 84 mg kg^− 1 d.w. in roots and from 0.020 to 6.9 mg kg^− 1 d.w. in shoots. OrgHg concentrations in soils varied between 0.20 and 130 μg kg^− 1 d.w. representing on average 0.13% of the total Hg (THg). In root and shoot samples OrgHg comprised on average 0.58% (roots) and 0.66% (shoots) of THg. Average bioaccumulation factors (BAFs) for OrgHg in relation to soil concentrations were 3.3 (for roots) and 1.5 (for shoots).The daily intake (DI) of THg in 33 sampling sites exceeded the acceptable daily intake (ADI) of THg of both cows (ADI = 1.4 mg d^− 1) and sheep (ADI = 0.28 mg d^− 1), in view of food safety associated with THg in animal kidneys. Estimated DI of OrgHg for grazing animals were up to 220 μg d^− 1 (for cows) and up to 33 μg d^− 1 (for sheep).This study suggested that solely monitoring the levels of THg in soils and feed may not allow to adequately taking into account accumulation of OrgHg in feed crops and properly address risks associated with OrgHg exposure for animals and humans. Hence, the inclusion of limits for OrgHg in feed quality and food safety legislation is advised.     

From the shop to the drain — Volatile methylsiloxanes in cosmetics and personal care products

Organosiloxanes are widely used in the formulation of a broad range of cosmetic and personal care products (PCPs), including creams and lotions, bath soaps, shampoo and hair care products to soften, smooth, and moisten. In fact, the intensive and widespread use of organosiloxanes combined with their lipophilic nature, makes them interesting targets for future research, particularly in the toxicology area.This study focused on determining the concentration levels of these compounds in the bestselling brands of PCPs in the Oporto region (Portugal), allowing the estimation of dermal and inhalation exposure to siloxanes and the evaluation of the quantities released to the environment “down-the-drain” and to air. To accomplish this task, a QuEChERS technique (“Quick, Easy, Cheap, Effective, Rugged, and Safe”) was employed to extract the siloxanes from the target PCPs, which has never been tested before. The resulting extract was analysed by gas chromatography–mass spectrometry (GC–MS). The limits of detection varied between 0.17 (L2) and 3.75 ng g^− 1 (L5), being much lower than any values reported in the literature for this kind of products. In general, satisfactory precision (< 10%) and accuracy values (average recovery of 84%) were obtained.123 PCPs were analysed (moisturizers, deodorants, body and hair washes, toilet soaps, toothpastes and shaving products) and volatile methylsiloxanes were detected in 96% of the samples, in concentrations between 0.003 μg g^− 1 and 1203 μg g^− 1. Shampoo exhibited the highest concentration for cyclic and aftershaves for linear siloxanes. Combining these results with the daily usage amounts, an average daily dermal exposure of 25.04 μg kg_bw^− 1 day^− 1 for adults and 0.35 μg kg_bw^− 1 day^− 1 for baby/children was estimated. The main contributors for adult dermal exposure were body moisturizers, followed by facial creams and aftershaves, while for babies/children were body moisturizers, followed by shower gel and shampoo. Similarly, the average daily inhalation exposure was also estimated. Values of 1.56 μg kg_bw^− 1 day^− 1 for adults and 0.03 μg kg_bw^− 1 day^− 1 for babies/children were calculated. An estimate of the siloxanes amount released “down-the-drain” into the sewage systems through the use of toiletries was also performed. An emission per capita between 49.25 and 9574 μg day^− 1 (mean: 1817 μg day^− 1) is expected and shampoo and shower gel presented the higher mean total values (1008 μg day^− 1 and 473.3 μg day^− 1, respectively). In the worst-case scenario, D5 and D3 were the predominant siloxanes in the effluents with 3336 μg day^− 1 and 3789 μg day^− 1, respectively. Regarding the air emissions per capita, values between 8.33 and 6109 μg day^− 1 (mean: 1607 μg day^− 1) are expected and D5 and D6 were the predominant siloxanes.     

Body burden of metals and persistent organic pollutants among Inuit in the Canadian Arctic

Inuit living in the Arctic are exposed to elevated levels of environmental contaminants primarily due to long-range atmospheric transport. Blood sampling and contaminant biomonitoring was conducted as part of the International Polar Year Inuit Health Survey in 2007-2008. The body burden of metals (e.g. Cd, Pb) and persistent organic pollutants (e.g. PCBs, DDT & DDE, toxaphene, chlordane, PBDEs) were measured for Inuit participants (n = 2172) from 36 communities in Nunavut, Nunatsiavut, and the Inuvialuit Settlement Region, in Canada. The geometric mean of blood concentrations for Cd, Pb, PCBs, DDE & DDT, toxaphene, and chlordane were higher than those in the Canadian general population. A total of 9% of study participants exceeded the intervention guideline of 100 μg L^− 1 for Pb, 11% of participants exceeded the trigger guideline of 5 μg L^− 1 for Cd, and 1% exceeded the intervention guideline of 100 μg L^− 1 for PCBs. Also, 3% of women of child-bearing age exceeded blood Pb of 100 μg L^− 1 while 28% of women of child-bearing age exceeded 5 μg L^− 1 of PCBs. This work showed that most Inuit Health Survey participants were below blood contaminant guidelines set by Health Canada but that metal and POP body burdens commonly exceed exposures observed in the general population of Canada.     

Route-specific daily uptake of organochlorine pesticides in food,dust, and air by Shanghai residents,China

Dichlorodiphenyltrichloroethane (DDT) and hexachlorocyclohexanes (HCHs) are widely detected in the environment, although they have been banned in China since 1980s. To better understand the route-specific daily uptake of the pesticides by humans, a total of 322 food, dust, and air samples were collected in Shanghai, China, during 2008–2011. The median concentrations were 0.2–126.6 and 0.03–1.6 ng/g wet weight for DDTs (DDT and its metabolites) and HCHs, respectively, in different types of foods. The values in dust (indoors and outdoors) were 5.7–29.8 and 1.3–5.4 ng/g, and 13.9 × 10^− 3 and 2.6 × 10^− 3 ng/m³ in air (gas + particle) for DDTs and HCHs, respectively. The daily uptake of a pesticide by humans was calculated via the pesticide intake multiplied by its uptake efficiency. The uptake efficiencies of DDTs and HCHs in food through human intestines were estimated using bioaccessibility measured via an in vitro method simulating the human gastrointestinal digestion process. The total daily uptakes of DDTs and HCHs through three routes (i.e., ingestion, inhalation, and dermal contact) were 79.4 and 4.9 ng/day, respectively, for children, and 131.1 and 8.0 ng/day, respectively, for adults. Ingestion via food and dust was the main route of human exposure to the pesticides, and the daily uptake of the pesticides via food consumption accounted for 95.0–99.2% of the total.     

Aggregate consumer exposure to UV filter ethylhexyl methoxycinnamate via personal care products

Ultraviolet (UV) filters are substances designed to protect our skin from UV-induced damage and can be found in many categories of personal care products (PCPs). The potential endocrine-disrupting effects attributed to UV filter ethylhexyl methoxycinnamate (EHMC) are being debated. We evaluated the aggregate exposure of the Swiss–German population (N = 1196; ages ≤ 1–97 years) to EHMC via the use of PCPs; thus we provide the first comprehensive information about the current EHMC exposure sources and aggregate exposure levels. In our probabilistic modeling method performed at an individual level, PCP use data obtained by a postal questionnaire were linked to concentration data on EHMC gained from chemical analyses of PCPs used by the questionnaire respondents. The modeled median and 99.9th percentile of the internal aggregate exposure for the general population were 0.012 and 0.873 mg day^− 1 kg^− 1 and 0.008 and 0.122 mg day^− 1 kg^− 1 for the summer/autumn and winter/spring period, respectively. The major contributors to internal aggregate exposure were sunscreen products in summer/autumn (females: 64%; males: 85%; children aged ≤ 12 years 93%). In winter/spring, lip care dominated for females (30%) and sunscreen for males (38%) and children aged ≤ 12 years (50%). Overall, the internal aggregate exposure estimates for the studied population are shown to be below the Derived No Effect Level (DNEL) for EHMC i.e., the level of exposure above which humans should not be exposed; however, when an intense short-term exposure via sunscreen is accounted for during a sunbathing day, at the high-end percentiles (99.9th) the predicted aggregate exposure exceeds the DNEL for thyroid-disrupting effects such as for children aged ≤ 4 years, who might be particularly susceptible to endocrine disrupting events. It is nevertheless critical to acknowledge that quantitative data on transdermal penetration of EHMC from PCPs are currently insufficient. Since long-term effects of endocrine disruptors are not known, future studies are warranted to provide accurate quantitative data on transdermal penetration of EHMC and to determine its metabolic fate in humans.     

Are Chinese consumers at risk due to exposure to metals in crayfish? A bioaccessibility-adjusted probabilistic risk assessment

Freshwater crayfish, the world's third largest crustacean species, has been reported to accumulate high levels of metals, while the current knowledge of potential risk associated with crayfish consumption lags behind that of finfish. We provide the first estimate of human health risk associated with crayfish (Procambarus clarkii) consumption in China, the world's largest producer and consumer of crayfish. We performed Monte Carlo Simulation on a standard risk model parameterized with local data on metal concentrations, bioaccessibility (φ), crayfish consumption rate, and consumer body mass. Bioaccessibility of metals in crayfish was found to be variable (68–95%) and metal-specific, suggesting a potential influence of metal bioaccessibility on effective metal intake. However, sensitivity analysis suggested risk of metals via crayfish consumption was predominantly explained by consumption rate (explaining > 92% of total risk estimate variability), rather than metals concentration, bioaccessibility, or body mass. Mean metal concentrations (As, Cd, Cu, Ni, Pb, Se and Zn) in surveyed crayfish samples from 12 provinces in China conformed to national safety standards. However, risk calculation of φ-modified hazard quotient (HQ) and hazard index (HI) suggested that crayfish metals may pose a health risk for very high rate consumers, with a HI of over 24 for the highest rate consumers. Additionally, the φ-modified increased lifetime risk (ILTR) for carcinogenic effects due to the presence of As was above the acceptable level (10^− 5) for both the median (ILTR = 2.5 × 10^− 5) and 90th percentile (ILTR = 1.8 × 10^− 4), highlighting the relatively high risk of As in crayfish. Our results suggest a need to consider crayfish when assessing human dietary exposure to metals and associated health risks, especially for high crayfish-consuming populations, such as in China, USA and Sweden.     

Rice consumption contributes to low level methylmercury exposure in southern China

Fish consumption is considered as the primary pathway of human methylmercury (MeHg) exposure. However, recent studies highlighted that, rice, rather than fish, is the main route of human MeHg exposure in Guizhou, inland China. China is considered as the largest anthropogenic source of mercury (Hg) emission in the world, which has led to serious environmental Hg pollution. But there are no comprehensive studies regarding this environmental health problem to evaluate human Hg exposure and associated health effects. This study aimed to estimate daily MeHg intake and health risk in 7 provinces in southern China, and to assess the relative contribution from rice and fish consumption. The average levels of total mercury (THg) and MeHg in rice samples were generally low at 10.1 ng·g^− 1 and 2.47 ng·g^− 1, respectively. But a total of 36 rice samples (12.7%) had THg concentration exceeding the national limit (20 ng·g^− 1). Generally, rural population had significantly higher Probable Daily Intakes (PDIs) of MeHg than urban population from rice consumption and its relative contribution to MeHg exposure increased significantly from coastal to inland area. The averages of PDIs of MeHg were 0.020 μg·kg^− 1·d^− 1 and 0.028 μg·kg^− 1·d^− 1 for urban and rural population in southern China, respectively. Despite the serious environmental Hg pollutions in China, the general population in southern China had low risk of MeHg exposure. But rice is an important route of human MeHg exposure in southern China, especially for the rural population in inland area. The findings indicate that rice consumption should be considered when evaluating MeHg exposure in rice eating population in southern China.     

Levels and profiles of PCDD/Fs,PCBs in mothers' milk in Shenzhen of China: Estimation of breast-fed infants’ intakes

Sixty breast milk samples were collected in Shenzhen, China from July to November in 2007. The samples were analyzed of the concentrations of polychlorinated dibenzo-p-dioxins (PCDDs), polychlorinated dibenzofurans (PCDFs) and polychlorinated biphenyls (PCBs). The range of upper-bound for ∑ TEQ-(PCDD/Fs + PCBs) in the samples was 4.10–35.3 pg TEQ g^− 1 lipid (median: 10.6 pg TEQ g^− 1 lipid; mean: 11.9 pg TEQ g^− 1 lipid). The levels of the measured contaminants in the breast milk had significant correlations with the length of inhabitation period in Shenzhen (r = 0.487, p < 0.05 for PCDD/Fs, r = 0.431, p < 0.05 for PCBs and r = 0.478, p < 0.05 for ∑ TEQ-(PCDD/Fs + PCBs)), and the consumption rate of fish (r = 0.366, p < 0.05 for PCDD/Fs, r = 0.486, p < 0.05 for PCBs and r = 0.416, p < 0.05 for ∑ TEQ-(PCDD/Fs + PCBs)), respectively. Moreover, significant positive correlations were also detected between the participant's age (r = 0.305, p < 0.05 for ∑ TEQ-PCBs and r = 0.275, p < 0.05 for ∑ TEQ-(PCDD/Fs + PCBs)) and the body burdens of these contaminants respectively. It is estimated that the daily intake (EDI) of the sum of PCDD/Fs and DL-PCBs by the breast-fed infants was 5.60–161 pg TEQ kg^− 1 bw per day (mean: 48.2 pg TEQ kg^− 1 bw per day; median: 42.2 pg TEQ kg^− 1 bw per day). The result showed that both the body burdens of PCDD/Fs and PCBs of the recruit population and the calculated EDI of the breast-fed infants were higher than those in the non-exposed areas in mainland China. This suggests that continuous surveillance on PCDD/Fs and PCBs levels in human milk is critical to more precisely evaluate the human health risk posed by the negative environmental impact in Shenzhen in the future.     

Monocyclic and bicyclic monoterpenes in air of German daycare centers and human biomonitoring in visiting children,the LUPE 3 study

To investigate the assumed association between indoor air pollution with monoterpenes (MTps) and the internal MTp exposure of occupants, a comparative study was performed in daycare centers in two federal states of Germany. Three well-known monoterpenoid air pollutants, viz. α-pinene (αPN), Δ³-carene (CRN), and R-limonene (LMN), were measured in indoor air in 45 daycare centers. Additionally, urine samples of 222 children visiting these facilities were collected in the evening after a full-day stay. Altogether 11 MTp metabolites were analyzed in the urine samples using a novel highly sensitive and selective gas chromatographic–tandem-mass spectrometric procedure. The medians (95th percentiles) of the MTp levels in indoor air were 9.1 μg m^− 3 (94 μg m^− 3) for LMN, 2.6 μg m^− 3 (13 μg m^− 3) for αPN, and < 1.0 μg m^− 3 (3.2 μg m^− 3) for CRN. None of the day care centers exceeded the German health precaution or hazard guide value. In spite of the low MTp air exposure, the urine analyses revealed an exposure to the three monoterpenes in almost all children. The median levels of MTp metabolites in urine were 0.11 mg L^− 1 for LMN-8,9-OH, 0.10 mg L^− 1 for LMN-1,2-OH, 49 μg L^− 1 for PA, 2.9 μg L^− 1 for POH, 5.2 μg L^− 1 for tCAR, and 4.1 μg L^− 1 for cCAR (LMN metabolites), 7.2 μg L^− 1 for MYR, 19 μg L^− 1 for tVER, and 19 μg L^− 1 for cVER (αPN metabolites), as well as 8.2 μg L^− 1 for CRN-10-COOH (CRN metabolite). Statistically significant and strong correlations among the urinary metabolites of each MTp were found. Moreover, statistical associations between LMN metabolites and the LMN indoor air levels were revealed. However, the weakness of the associations indicates a considerable impact of other MTp sources, e.g. diet and consumer products, on the internal exposure.     

Associations between short/medium-term variations in black smoke air pollution and mortality in the Glasgow conurbation,UK

ObjectivesTo examine associations between short/medium-term variations in black smoke air pollution and mortality in the population of Glasgow and the adjacent towns of Renfrew and Paisley over a 25-year period at different time lags (0–30 days).MethodsGeneralised linear (Poisson) models were used to investigate the relationship between lagged black smoke concentrations and daily mortality, with allowance for confounding by cold temperature, between 1974 and 1998.ResultsWhen a range of lag periods were investigated significant associations were noted between temperature-adjusted black smoke exposure and all-cause mortality at lag periods of 13–18 and 19–24 days, and respiratory mortality at lag periods of 1–6, 7–12, and 13–18 days. Significant associations between cardiovascular mortality and temperature-adjusted black smoke were not observed. After adjusting for the effects of temperature a 10 μg m^− 3 increase in black smoke concentration on a given day was associated with a 0.9% [95% Confidence Interval (CI): 0.3–1.5%] increase in all cause mortality and a 3.1% [95% CI: 1.4–4.9%] increase in respiratory mortality over the ensuing 30-day period. In contrast for a 10 μg m^− 3 increase in black smoke concentration over 0–3 day lag period, the temperature adjusted exposure mortality associations were substantially lower (0.2% [95% CI: − 0.0–0.4%] and 0.3% [95% CI: − 0.2–0.8%] increases for all-cause and respiratory mortality respectively).ConclusionsThis study has provided evidence of association between black smoke exposure and mortality at longer lag periods than have been investigated in the majority of time series analyses.     

Radium dial watches,a potentially hazardous legacy?

This study re-examines the risk to health from radium (²²⁶Ra) dial watches. Ambient dose equivalent rates have been measured for fifteen pocket watches giving results of up to 30 μSv h^− 1 at a distance of 2 cm taken with a series 1000 mini-rad from the front face (arithmetic mean ambient dose equivalent for pocket watches being 13.2 μSv h^− 1). A pocket compass gave rise to a similar ambient dose equivalent rate, of 20 μSv h^− 1, to the pocket watches, with its cover open. Eighteen wristwatches have also been assessed, but their dose rates are generally much lower (the arithmetic mean being 3.0 μSv h^− 1), although the highest ambient dose equivalent rate noted was 20 μSv h^− 1. A phantom experiment using a TLD suggested an effective dose equivalent of 2.2 mSv/y from a 1 μCi (37 kBq) radium dial worn for 16 h/day throughout the year (dose rate 0.375 μSv h^− 1). For this condition we estimated maximum skin dose for our pocket watches as 16 mSv per year, with effective doses of 5.1 mSv and 1.169 mSv when worn in vest and trouser pockets respectively. This assumes exposure from the back of the watch which is generally around 60–67% of that from the front. The maximum skin dose from a wristwatch was 14 mSv, with 4.2 mSv effective dose in vest pocket. Radium (²²⁶Ra) decays to the radioactive gas radon (²²²Rn), and atmospheric radon concentration measurements taken around a pocket watch in a small sealed glass sphere recorded 18,728 Bq m^− 3. All watches were placed in a room with a RAD7 real-time radon detector. Radon concentration average was 259 ± 9 Bq m^− 3 over 16 h, compared to background average over 24 h of 1.02 Bq m^− 3. Over 6 weeks highs of the order of 2000 Bq m^− 3 were routinely recorded when the heating/ventilation system in the room was operating at reduced rates, peaking at over 3000 Bq m^− 3 on several occasions. Estimates of the activity of ²²⁶Ra in the watches ranged from 0.063 to 1.063 μCi (2.31 to 39.31 kBq) for pocket watches and from 0.013 to 0.875 μCi (0.46 to 32.38 kBq) for wrist watches. The risk from old watches containing radium appears to have been largely forgotten today. This paper indicates a health risk, particular to collectors, but with knowledge and appropriate precautions the potential risks can be reduced.     

Measurement and health risk assessment of PM2.5, flame retardants,carbonyls and black carbon in indoor and outdoor air in kindergartens in Hong Kong

Indoor air pollution is closely related to children's health. Polybrominated diphenyl ethers (PBDEs) and dechlorane plus (DP) transmitted through indoor PM_2.5 and dust, along with carbonyl compounds and black carbon (BC) aerosol were analysed in five Hong Kong kindergartens. The results showed that 60% of the median PM_2.5 levels (1.3 × 10¹ to 2.9 × 10¹ μg/m³ for indoor; 9.5 to 8.8 × 10¹ μg/m³ for outdoor) in the five kindergartens were higher than the guidelines set by the World Health Organization (2.5 × 10¹ μg/m³). Indoor PM_2.5 mass concentrations were correlated with outdoor PM_2.5 in four of the kindergartens. The PBDEs (0.10–0.64 ng/m³ in PM_2.5; 0.30–2.0 × 10² ng/g in dust) and DP (0.05–0.10 ng/m³ in PM_2.5; 1.3–8.7 ng/g in dust) were detected in 100% of the PM_2.5 and dust samples. Fire retardant levels in the air were not correlated with the levels of dust in this study. The median BC concentrations varied by > 7-fold from 8.8 × 10² ng/m^− 3 to 6.7 × 10³ ng/m^− 3 and cooking events might have caused BC concentrations to rise both indoors and outdoors. The total concentrations of 16 carbonyls ranged from 4.7 × 10¹ μg/m³ to 9.3 × 10¹ μg/m³ indoors and from 1.9 × 10¹ μg/m³ to 4.3 × 10¹ μg/m³ outdoors, whilst formaldehyde was the most abundant air carbonyl. Indoor carbonyl concentrations were correlated with outdoor carbonyls in three kindergartens. The health risk assessment showed that hazard indexes (HIs) HIs of non-cancer risks from PBDEs and DPs were all lower than 0.08, whilst non-cancer HIs of carbonyl compounds ranged from 0.77 to 1.85 indoors and from 0.50 to 0.97 outdoors. The human intake of PBDEs and DP through inhalation of PM_2.5 accounted for 78% to 92% of the total intake. The cancer hazard quotients (HQs) of formaldehyde ranged from 4.5E − 05 to 2.1E − 04 indoors and from 1.9E − 05 to 6.2E − 05 outdoors. In general, the indoor air pollution in the five Hong Kong kindergartens might present adverse effects to children, although different schools showed distinct pollution levels, so indoor air quality might be improved through artificial measures. The data will be useful to developing a feasible management protocol for indoor environments.     

Association between maternal exposure to perfluorooctanoic acid (PFOA) from electronic waste recycling and neonatal health outcomes

ObjectivePerfluorooctanoic acid (PFOA) has applications in numerous industrial and consumer products. The widespread prevalence of PFOA in humans demonstrated in recent studies has drawn considerable interest from the public. We aimed to evaluate the exposure of mothers to PFOA and the potential hazards to neonates in a primitive electronic waste recycling area, Guiyu, China, and a control area, Chaonan, China.MethodsOur investigation included analyses of maternal serum samples, health effect examinations, and other relevant factors. Questionnaires were administered and maternal serum samples were collected for 167 pregnant women. Solid phase extraction method was used for all analytical sample preparation, and analyses were completed using high performance liquid chromatography tandem mass spectrometry method.ResultsThe PFOA concentration was higher in maternal serum samples from Guiyu than in samples from Chaonan (median 16.95, range 5.5–58.5 ng mL^− 1; vs. 8.7, range 4.4–30.0 ng mL^− 1; P < 0.001). Residence in Guiyu, involvement in e-waste recycling, husband's involvement in e-waste and use of the family residence as workshop were significant factors contributing to PFOA exposure. Maternal PFOA concentrations were significantly different between normal births and adverse birth outcomes including premature delivery, term low birth weight, and stillbirths. After adjusting for potential confounders, PFOA was negatively associated with gestational age [per lg-unit: β = − 15.99 days, 95% confidence interval (CI), − 27.72 to − 4.25], birth weight (per lg-unit: β = − 267.3 g, 95% CI, − 573.27 to − 37.18), birth length (per lg-unit: β = − 1.91 cm, 95% CI, − 3.31 to − 0.52), and Apgar scores (per lg-unit: β = − 1.37, 95% CI, − 2.42 to − 0.32), but not associated with ponderal index.ConclusionsMothers from Guiyu were exposed to higher levels of PFOA than those from control areas. Prenatal exposure to PFOA was associated with decreased neonatal physical development and adverse birth outcomes.     

The bioaccessibility of polychlorinated biphenyls (PCBs) and polychlorinated dibenzo-p-dioxins/furans (PCDD/Fs) in cooked plant and animal origin foods

In this study, we compared the effect of boiling and frying food preparation methods in determining the bioaccessibility of polychlorinated biphenyls (PCBs) and polychlorinated dibenzo-p-dioxins/furans (PCDD/Fs) in rice, cabbage, milk powder, eggs, beef, and fresh water fish. We then used these data to calculate a toxic equivalent (TEQ) for risk assessment and compared it to published values that did not account for bioaccessibility.When the foods were prepared by boiling, the mean bioaccessibility (%) in rice (PCBs: 16.5 ± 1.0, PCDD/Fs: 4.9 ± 0.3) and cabbage (PCBs: 4.2 ± 0.9, PCDD/Fs: 1.9 ± 0.7) were lower than in animal origin foods (beef, PCBs: 49.0 ± 3.3, PCDD/Fs: 7.8 ± 0.9; egg, PCBs: 29.7 ± 3.1, PCDD/Fs: 8.6 ± 1.3; fish, PCBs: 26.9 ± 2.5, PCDD/Fs: 7.9 ± 1.3; milk powder, PCBs: 72.3 ± 1.6, PCDD/Fs: 28.4 ± 1.2).When fried in cooking oil, the bioaccessibilities of all analytes in all foods increased, but the increase in plant based foods (rice, PCBs: 3.4 ×, PCDD/Fs: 3.6 ×; cabbage, PCBs: 10.3 ×, PCDD/Fs: 7.9 ×) was greater than that of animal origin foods (beef, PCBs: 1.6 ×, PCDD/Fs: 3.4 ×; egg, PCBs: 2.1 ×, PCDD/Fs: 1.8 ×; fish, PCBs: 2.8, PCDD/Fs: 3.2 ×).Comparison of PCBs/PCDD/Fs bioaccessibility in rice and cabbage showed that bioaccessibility was greater in the low fat, high carbohydrate/protein content food (rice) than in the low carbohydrate/protein, low fat content food (cabbage), regardless of the method used to prepare the food.Adjusting for bioaccessibility reduced the gross estimated daily intake (EDI) of 112 pg WHO-TEQ/day, by 88% and 63% respectively for foods prepared by boiling and frying.Our results indicate that: 1) The method used for cooking is an important determinant of PCBs/PCDD/Fs bioaccessibility, especially for plant origin foods, 2) there might be a joint fat, carbohydrate and protein effect that influences the bioaccessibilities of PCBs/PCDD/Fs in foods, and 3) use of bioaccessibility estimates would reduce the uncertainty in TEQ calculations.     

Polybrominated diphenyl ethers (PBDEs) in human samples of mother–newborn pairs in South China and their placental transfer characteristics

There are limited data concerning the placenta transfer characteristics and accumulation of polybrominated diphenyl ethers (PBDEs) in infants. However, PBDEs received increasing health concerns due to their endocrine disrupt and neurodevelopment toxicity effects. The present study assessed the accumulation of PBDEs in 30 paired placenta, breast milk, fetal cord blood, and neonatal urine samples collected from five major cities of the South China. The age of mothers ranged from 21 to 39 (mean 27.6 ± 4.56). The ∑ PBDE concentrations were 15.8 ± 9.88 ng g^− 1 lipid in placenta, 13.2 ± 7.64 ng g^− 1 lipid in breast milk, 16.5 ± 19.5 ng g^− 1 lipid in fetal cord blood, and 1.80 ± 1.99 ng ml^− 1 in neonatal urine. BDE-47 was the predominant congener in all types of human sample. Octa-BDEs such as BDE-196/-197 were detected highly in placenta and cord blood while moderately in breast milk and neonatal urine. Significant (p < 0.01) correlations were observed for both total and most individual PBDEs in cord blood–maternal placenta and breast milk–urine paired individual samples. The extent of placental transfer of higher brominated BDEs such as BDE-196/-197 was greater than that of BDE-47. The estimated daily intake (EDI) analysis for breast-fed infants revealed that newborns in these areas were exposed to relatively high levels of PBDEs via breast milk. Our study not only provided systematic fundamental data for PBDE distribution but also revealed the placenta transfer characteristics of PBDE congeners in South China.     

Can car air filters be useful as a sampling medium for air pollution monitoring purposes?

Urban air quality and real human exposure to chemical environmental stressors is an issue of high scientific and political interest. In an effort to find innovative and inexpensive means for air quality monitoring, the ability of car engine air filters (CAFs) to act as efficient samplers collecting street level air, to which people are exposed to, was tested. In particular, in the case of taxis, air filters are replaced after regular distances, the itineraries are almost exclusively urban, cruising mode is similar and, thus, knowledge of the air flow can provide with an integrated city air sample. The present pilot study focused on polycyclic aromatic hydrocarbons (PAHs), the most important category of organic pollutants associated with traffic emissions. Concentrations of ΣPAHs in CAFs ranged between 650 and 2900 μg CAF^− 1, with benzo[b]fluoranthene, benzo[k]fluoranthene and indeno[123-cd]pyrene being the most abundant PAHs. Benzo[a]pyrene (BaP) ranged between 110 and 250 μg CAF^− 1, accounting regularly for 5–15% of the total carcinogenic PAHs. The CAF PAH loads were used to derive road-level atmospheric PAH concentrations from a standard formula relating to the CAF air flow. Important parameters/assumptions for these estimates are the cruising speed and the exposure duration of each CAF. Based on information obtained from the garage experts, an average ‘sampled air volume’ of 48,750 m³ per CAF was estimated, with uncertainty in this calculation estimated to be about a factor of 4 between the two extreme scenarios. Based on this air volume, ΣPAHs ranged between 13 and 56 ng m^− 3 and BaP between 2.1 and 5.0 ng m^− 3, suggesting that in-traffic BaP concentrations can be many times higher than the limit values set by the UK (0.25 ng m^− 3) and the European Union (1.0 ng m^− 3), or from active sampling stations normally cited on building roof tops or far from city centres.Notwithstanding the limitations of this approach, the very low cost, the continuous availability of very high amounts of “sample”, and the “retroactivity” render it very useful and complementary to existing passive sampling techniques. This approach yields estimated air concentrations that reflect the pollutant concentrations to which taxi drivers, pedestrians, cyclists and road-related professionals are exposed.     

Anthropogenic radionuclides in sediment in the Japan Sea: distribution and transport processes of particulate radionuclides

Distributions of anthropogenic radionuclides (⁹⁰Sr, ¹³⁷Cs and ^239+240Pu) in seabed sediment in the Japan Sea were collected during the period 1998–2002. Concentration of ⁹⁰Sr, ¹³⁷Cs and ^239+240Pu in seabed sediment was 0.07–1.6 Bq kg⁻¹, 0.4–9.1 Bq kg⁻¹ and 0.002–1.9 Bq kg⁻¹, respectively. In the northern basin of the sea (Japan Basin), ^239+240Pu/¹³⁷Cs ratios in seabed sediment were higher and their variation was smaller compared to that in the southeastern regions of the sea. The higher ^239+240Pu/¹³⁷Cs ratios throughout the Japan Basin were considered to reflect production of Pu-enriched particles in the surface layer and substantial sinking of particulate materials in this region. In the southern regions of the Japan Sea (<38°N), both inventories and ^239+240Pu/¹³⁷Cs ratios in sediment were larger than those in the other regions. In the southern Japan Sea, observations suggested that supply of particulate radionuclides by the Tsushima Warm Current mainly enhanced accumulation of the radionuclides in this region.     

The ‘take home’ burden of workplace sensitizers: Flour contamination in bakers' families

BackgroundExposure to flour/flour constituents is a leading cause of occupational asthma. Paternal occupational exposure to flour has been associated with increased likelihood of childhood asthma, raising the possibility of para-occupational exposure whereby family members are exposed to sensitizers ‘taken home’ on contaminated skin/clothing.ObjectiveTo establish whether workplace contamination of skin/clothing with wheat flour allergen (WFA) and fungal α-amylase (FAA) is associated with increased levels of these allergens in bakers' homes.MethodsBakeries in north-east Scotland were invited to participate. Control subjects were recruited from University of Aberdeen staff and students. Exposure assessment was carried out in bakeries, bakers' cars and the homes of bakers and controls using surface wipe and vacuum sampling; samples were analyzed for total protein, FAA and WFA.Results164 wipe samples and 49 vacuum samples were collected from 38 bakers (from 5 bakeries) and 10 controls.Compared to non-bakers, bakers had higher median levels of WFA and FAA in house vacuum samples; the difference was statistically significant for WFA/total protein (515.8 × 10^− 6 vs. 163.7 × 10^− 6, p = 0.031), FAA/total protein ratios (1.45 × 10^− 6 vs. 0.04 × 10^− 6, p < 0.001) and FAA loading (median 1.2 pg/cm² vs. 0.1 pg/cm², p < 0.001) with workplace exposure–home contamination relationships between bakers with higher and lower workplace contamination.We found positive correlations between WFA contamination of the bakers' foreheads and cars (r_s0.57, p = 0.028), foreheads and houses (r_s0.46, p = 0.025), shoes and houses (r_s0.45, p = 0.029); and between FAA contamination of shoes and houses (r_s0.46, p = 0.023), and cars and houses (r_s0.70, p = 0.008). There was no evidence of bakers using work-sourced flour for domestic baking.ConclusionsThis work demonstrates pathways for ‘take home’ exposure of occupationally sourced flour. Taken with our previous work, showing that bakers' children are more likely to have asthma, this supports the need for further investigation to establish whether ‘take home’ of occupationally sourced flour is widespread with health consequences.     

Radionuclide concentrations in soil and lifetime cancer risk due to gamma radioactivity in Kirklareli,Turkey

The objective of this study is to evaluate and map soil radionuclides' activity concentrations and environmental outdoor gamma dose rates (terrestrial and cosmic) in Kirklareli, Turkey. The excess lifetime cancer risks are also calculated. Outdoor gamma dose rates were determined in 230 sampling stations and soil samples were taken from 177 locations. The coordinates of the readings were determined by the Global Positioning System (GPS). The outdoor gamma dose rates were determined by Eberline smart portable device (ESP-2) and measurements were taken in air for two minutes at 1 m from the ground. The average outdoor gamma dose rate was 118 ± 34 nGy h^?1. Annual effective gamma dose of Kirklareli was 144 μSv and the excess lifetime cancer risk of 5.0 × 10^?4. Soil samples were analyzed by gamma spectroscopy. The average ²²⁶Ra, ²³⁸U, ²³²Th, ¹³⁷Cs, and ⁴⁰K activities were 37 ± 18 Bq kg^?1, 28 ± 13 Bq kg^?1, 40 ± 18 Bq kg^?1, 8 ± 5 Bq kg^?1 and 667 ± 281 Bq kg^?1, respectively. The average soil radionuclides' concentrations of Kirklareli were within the worldwide range although some extreme values had been determined. Annual effective gamma doses and the excess lifetime risks of cancer were higher than the world's average.     

Brominated and chlorinated flame retardants in San Francisco Bay sediments and wildlife

Restrictions on the use of polybrominated diphenyl ethers (PBDEs) have resulted in the use of alternative flame retardants in consumer products to comply with flammability standards. In contrast to PBDEs, information on the occurrence and fate of these alternative compounds in the environment is limited, particularly in the United States. In this study, a survey of flame retardants in San Francisco Bay was conducted to evaluate whether PBDE replacement chemicals and other current use flame retardants were accumulating in the Bay food web. In addition to PBDEs, brominated and chlorinated flame retardants (hexabromocyclododecane (HBCD) and Dechlorane Plus (DP)) were detected in Bay sediments and wildlife. Median concentrations of PBDEs, HBCD, and DP, respectively, were 4.3, 0.3, and 0.2 ng g^− 1 dry weight (dw) in sediments; 1670, < 6.0, and 0.5 ng g^− 1 lipid weight (lw) in white croaker (Genyonemus lineatus); 1860, 6.5, and 1.3 ng g^− 1 lw in shiner surfperch (Cymatogaster aggregata); 5500, 37.4, and 0.9 ng g^− 1 lw in eggs of double-crested cormorant (Phalacrocorax auritus); 770, 7.1, and 0.9 ng g^− 1 lw in harbor seal (Phoca vitulina) adults; and 330, 3.5, and < 0.1 ng g^− 1 lw in harbor seal (P. vitulina) pups. Two additional flame retardants, pentabromoethylbenzene (PBEB) and 1,2-bis(2,4,6 tribromophenoxy)ethane (BTBPE) were detected in sediments but with less frequency and at lower concentrations (median concentrations of 0.01 and 0.02 ng g^− 1 dw, respectively) compared to the other flame retardants. PBEB was also detected in each of the adult harbor seals and in 83% of the pups (median concentrations 0.2 and 0.07 ng g^− 1 lw, respectively). The flame retardants hexabromobenzene (HBB), decabromodiphenyl ethane (DBDPE), bis(2-ethylhexyl) tetrabromophthalate (TBPH), and 2-ethylhexyl 2,3,4,5-tetrabromobenzoate (TBB), were not detected in sediments and BTBPE, HBB and TBB were not detected in wildlife samples. Elevated concentrations of some flame retardants were likely associated with urbanization and Bay hydrodynamics. Compared to other locations, concentrations of PBDEs in Bay wildlife were comparable or higher, while concentrations of the alternatives were generally lower. This study is the first to determine concentrations of PBDE replacement products and other flame retardants in San Francisco Bay, providing some of the first data on the food web occurrence of these flame retardants in a North American urbanized estuary.