Impact of pregnancy and other factors including smoking on the urinary levels of triclosan

Data from National Health and Nutrition Examination Survey were used to evaluate the impact of pregnancy on the levels of triclosan (TCS) in urine. Regression models were fitted to evaluate this association with adjustment for other factors that may affect the levels of TCS. Pregnant females had higher levels of TCS than non-pregnant females but the differences were not statistically significant. Levels of TCS were statistically significantly lower during the second trimester than during the third trimester. Smoking was associated with statistically significantly lower levels of TCS. The reasons for the association between smoking and the levels of TCS are not known. Further research is needed in this area.     

Trends over 1999–2014 in the concentrations of Ba,Cs, Co,Mo, Pb,Sb, Tl,and W in urine of US children aged 6–11 years

Data from National Health and Nutrition Examination Survey for children aged 6–11 years for 1999–2014 were used to study time trends and factors affecting the urinary levels of barium, cobalt, cesium, molybdenum, lead, antimony, thallium, and tungsten. Adjusted levels in urine declined every two years by 5.9% for barium, by 1.2% for cesium, by 18.2% for lead, and by 14% for antimony. For every additional smoker smoking inside a home, the levels of barium increased by 10.6% and for lead by 10%, but for tungsten levels decreased by 7.7%.     

Serum concentrations of persistent organic pollutants (POPs) in the inhabitants of a Sicilian city

Background

Polychlorinated biphenyls (PCBs) and organochlorine pesticides are common environmental contaminants that have been associated with human health problems.

Objectives

To assess serum concentrations of several organochlorine contaminants in general population living in a city with an ancient agricultural tradition and to identify possible exposure sources in Sicily.

Methods

A cross-sectional study was conducted on 101 individuals. Each participant answered a face-to-face questionnaire submitted by well-trained personnel and provided a serum sample which was analyzed for the concentrations of PCBs, HCB, HCHs and DDTs by using gas-chromatography coupled with mass spectrometry.

Results

HCB, p,p′-DDE, PCB 138, PCB 153 and PCB 180 were detected in more than 80% of the study participants. The ng g⁻¹ lipid median concentrations were: 18.6 for HCB; 175.1 for p,p′-DDE; 22. for PCB 138; 32.5 for PCB 153 and 23.0 for PCB 180. PCB 153 and PCB 138, PCB 138 and PCB 180, PCB 153 and PCB 180, and p,p′-DDE and HCB showed a high correlation each other (p < 0.05). HCB and p,p′-DDE concentrations were significantly higher in subjects >49 years old (adj-p = 0.03 in 50-69 years old and adj-p < 0.001 in >69 years old, respectively) whereas PCB 138, PCB 153 and PCB 180 concentrations were higher in males (adj-p = 0.03), in subjects >69 years old (adj-p = 0.04) and in current smokers (adj-p = 0.04).

Conclusions

The present study shows that serum concentrations of organochlorine compounds detected in subjects living in a small Sicilian city with ancient agricultural tradition are similar to those found in subjects living in urban areas of other countries. However, further investigations are needed to compare data from rural/urban areas in the same country, assessing correlations between serum concentrations of several chemical compounds and potential health effects in general population.     

Predictors of urinary bisphenol A and phthalate metabolite concentrations in Mexican children

Exposure to endocrine disrupting chemicals such as bisphenol A (BPA) and phthalates is prevalent among children and adolescents, but little is known regarding important sources of exposure at these sensitive life stages. In this study, we measured urinary concentrations of BPA and nine phthalate metabolites in 108 Mexican children aged 8–13 years. Associations of age, time of day, and questionnaire items on external environment, water use, and food container use with specific gravity-corrected urinary concentrations were assessed, as were questionnaire items concerning the use of 17 personal care products in the past 48-h. As a secondary aim, third trimester urinary concentrations were measured in 99 mothers of these children, and the relationship between specific gravity-corrected urinary concentrations at these two time points was explored. After adjusting for potential confounding by other personal care product use in the past 48-h, there were statistically significant (p < 0.05) positive associations in boys for cologne/perfume use and monoethyl phthalate (MEP), mono(3-carboxypropyl) phthalate (MCPP), mono(2-ethyl-5-hydroxyhexyl) phthalate (MEHHP), and mono(2-ethyl-5-oxohexyl) phthalate (MEOHP), and in girls for colored cosmetics use and mono-n-butyl phthalate (MBP), mono(2-ethylhexyl) phthalate (MEHP), MEHHP, MEOHP, and mono(2-ethyl-5-carboxypentyl) phthalate (MECPP), conditioner use and MEP, deodorant use and MEP, and other hair products use and MBP. There was a statistically significant positive trend for the number of personal care products used in the past 48-h and log-MEP in girls. However, there were no statistically significant associations between the analytes and the other questionnaire items and there were no strong correlations between the analytes measured during the third trimester and at 8–13 years of age. We demonstrated that personal care product use is associated with exposure to multiple phthalates in children. Due to rapid development, children may be susceptible to impacts from exposure to endocrine disrupting chemicals; thus, reduced or delayed use of certain personal care products among children may be warranted.     

Levels of selected urinary metabolites of volatile organic compounds in a representative sample of US adolescents

Data from National Health and Nutrition Examination Survey for the years 2011–2012 were used to evaluate the variability in the observed levels of 20 urinary metabolites of 16 parent volatile organic compounds by age, gender, race/ethnicity, and smoking status for adolescents aged 12–19 years. Smokers were found to have statistically significantly higher adjusted levels than nonsmokers for selected urinary metabolites of acrylonitrile (p < 0.05) and 1,3-butadiene (p < 0.05). For example, for N-Acetyl-S-(2-cyanoethyl)-L-cysteine, the adjusted levels for smokers were 29.2 ng/mL and 2.0 ng/mL for nonsmokers (p < 0.05). Females were found to have higher adjusted levels of selected metabolites of crotonaldehyde (p < 0.05), cyanide (p < 0.05), and tetrachloroethylene (p < 0.05) than males. For example, the adjusted levels of 2-Aminothiazoline-4-carboxylic acid or ATCA were 218.9 and 108.6 ng/mL for females and males, respectively (p < 0.05). Non-Hispanic whites (NHW) had higher adjusted levels than non-Hispanic blacks (NHB) for selected metabolites of N,N-dimethylformamide (p < 0.05) and ethylbenzene, styrene (p < 0.05). For example, for N-Acetyl-S-(N-methylcarbamoyl)-L-cysteine or AMCC, the adjusted levels for NHW and NHB were 122.7 and 80.2 ng/mL, respectively (p < 0.05). The reverse was true for selected metabolites of carbon-disulfide and tetrachloroethylene. For example, for N-Acetyl-S-(benzyl)-L-cysteine or BMA, adjusted levels for NHW and NHB were 6.7 and 10.3 ng/mL, respectively (p < 0.05).     

Assessment of the daily intake of 62 polychlorinated biphenyls from dietary exposure in South Korea

The dietary intake of polychlorinated biphenyls (PCBs) was estimated using the sum of 62 PCB congeners (∑₆₂PCBs), including seven indicator PCBs and 12 dioxin-like PCBs, in the South Korea. In this study, 200 individual food samples belonging to 40 different foodstuffs were investigated to estimate the distribution of PCB congeners in five sampling cities. PCB exposure was estimated using Korean dietary habits as established by the National Health and Nutrition Examination Survey (NHANES). The PCB concentrations in rice, the most frequently consumed food in Korea, was relatively low in whole food samples. The mean PCB levels measured in fish were the highest in this study, but each fish is consumed in relatively small amounts by the general population. Therefore, the daily dietary intake should also be considered with regard to human exposure to PCBs, especially with the consumption of contaminated foods. Dioxin-like PCB levels were also calculated using TEF values that were established in 2005. The average levels (pg TEQ/g) were 0.0002 for rice and 0.0098 for fish. The dioxin-like PCBs accounted for a relatively small percentage of the total PCBs, compared to previous studies. According to our research, the health risks associated with exposure to PCBs could be estimated using the tolerable daily intake (TDI) of the general population.     

Linking empirical estimates of body burden of environmental chemicals and wellness using NHANES data

Biomonitoring of industrial chemicals in human tissues and fluids has shown that all people carry a “body burden” of synthetic chemicals. Although measurement of an environmental chemical in a person's tissues/fluids is an indication of exposure, it does not necessarily mean the exposure concentration is sufficient to cause an adverse effect. Since humans are exposed to multiple chemicals, there may be a combination effect (e.g., additive, synergistic) associated with low-level exposures to multiple classes of contaminants, which may impact a variety of organ systems. The objective of this research is to link measures of body burden of environmental chemicals and a “holistic” measure of wellness. The approach is demonstrated using biomonitoring data from the National Health and Nutrition Examination Surveys (NHANES). Forty-two chemicals were selected for analysis based on their detection levels. Six biological pathway-specific indices were evaluated using groups of chemicals associated with each pathway. Five of the six pathways were negatively associated with wellness. Three non-zero interaction terms were detected which may provide empirical evidence of crosstalk across pathways. The approach identified five of the 42 chemicals from a variety of classes (metals, pesticides, furans, polycyclic aromatic hydrocarbons) as accounting for 71% of the weight linking body burden to wellness. Significant interactions were detected indicating the effect of smoking is exacerbated by body burden of environmental chemicals. Use of a holistic index on both sides of the exposure-health equation is a novel and promising empirical “systems biology” approach to risk evaluation of complex environmental exposures.