Personal care product use and urinary levels of phthalate metabolites in Mexican women

Sources of phthalates other than Polyvinyl chloride (PVC) related products are scarcely documented in Mexico. The objective of our study was to explore the association between urinary levels of nine phthalate metabolites and the use of personal care products. Subjects included 108 women who participated as controls in an ongoing population-based case-control study of environmental factors and genetic susceptibility to breast cancer in northern Mexico. Direct interviews were performed to inquire about sociodemographic characteristics, reproductive history, use of personal care products, and diet. Phthalate metabolites measured in urine by high performance liquid chromatography-isotope dilution tandem mass spectrometry were monoethyl phthalate (MEP), monobenzyl phthalate (MBzP), mono-n-butyl phthalate (MBP), mono-isobutyl phthalate (MiBP), mono-3-carboxypropyl phthalate (MCPP) as well as mono-2-ethylhexyl phthalate (MEHP), mono-2-ethyl-5-oxohexyl phthalate (MEOHP), mono-2-ethyl-5-hydroxyhexyl phthalate (MEHHP), mono-2-ethyl-5-carboxypentyl phthalate (MECPP) that are metabolites of di-ethylhexyl phthalate (DEHP). Detectable urinary concentrations of phthalate metabolites varied from 75% (MEHP) to 100% (MEP, MBP, MEOHP, MEHHP and MECPP). Medians of urinary concentrations of some phthalate metabolites were significantly higher among users of the following personal care products compared to nonusers: body lotion (MEHHP, MECPP and sum of DEHP metabolites (ΣDEHP)), deodorant (MEHP and ΣDEHP), perfume (MiBP), anti-aging facial cream (MEP, MBP and MCPP) and bottled water (MCPP, MEHHP and MEOHP). Urinary concentrations of MEP showed a positive relationship with the number of personal care products used. Our results suggest that the use of some personal care products contributes to phthalate body burden that deserves attention due to its potential health impact.     

Spatial and temporal variability of ²¹⁰Po and ²¹⁰Pb in mussels (Mytilus galloprovincialis) at the Turkish coast of the Aegean Sea

In this study, the activity concentrations of ²¹⁰Po and ²¹⁰Pb were determined in mussel samples (Mytilus galloprovincialis) collected from the Turkish coast of the Aegean Sea. The samples were collected seasonally for a period of two years (2004-2006) at six coastal stations (Çanakkale, Dikili, Foça, Çe?me, Didim, Bodrum). Mussels were separated into several groups according to their size (1-4, 4-6, >6 cm). The results showed that ²¹⁰Po concentrations in mussels varied between 53 ± 4 and 1960 ± 60 Bq kg⁻¹ dw. The highest activity ²¹⁰Po concentrations were determined in winter samples of mussels with a shell length of 4-6 cm from Didim. In general, it was observed that the ²¹⁰Pb concentration levels in mussels were lower than ²¹⁰Po concentrations. The ²¹⁰Po/²¹⁰Pb activity concentration ratios exceeded unity for all mussel samples and averaged 26.0. The inter-site differences seen in ²¹⁰Po concentrations can be due to both the natural background levels of sites and industrial activities.     

Gas phase precursors to anthropogenic secondary organic aerosol: Using the Master Chemical Mechanism to probe detailed observations of 1,3,5-trimethylbenzene photo-oxidation

A detailed gas-phase photochemical chamber box model, incorporating the Master Chemical Mechanism (MCMv3.1) degradation scheme for the model anthropogenic aromatic compound 1,3,5-trimethylbenzene, has been used to simulate data measured during a series of aerosol chamber experiments in order to evaluate the mechanism under a variety of VOC/NO_x conditions.The chamber model was used in the interpretation of comprehensive high (mass and time) resolution measurements of 1,3,5-trimethylbenzene and its photo-oxidation products recorded by a Chemical Ionisation Reaction Time-of-Flight Mass Spectrometer (CIR-TOF-MS). Supporting gas and aerosol measurements have also enabled us to explore the ‘missing link’ between the gas and aerosol phases. Model-measurement comparisons have been used to gain insight into the complex array of oxygenated products formed, including the peroxide bicyclic ring opening products (α,β-unsaturated-γ-dicarbonyls and furanones) and the O₂-bridged peroxide bicyclic ring-retaining products. To our knowledge this is the first time such high molecular weight species, corresponding to various peroxide bicyclic products represented in the MCMv3.1, have been observed in the gas-phase. The model was also used to give insight into which gas-phase species were participating in SOA formation, with the primary and secondary peroxide products, formed primarily under low NO_x conditions, identified as likely candidates.     

Ornamental Plants as Invasive Aliens: Problems and Solutions in Kruger National Park,South Africa

The most widespread invasive alien plant species in South Africa’s Kruger National Park (KNP) were either introduced unintentionally along rivers and roads, or intentionally for use as ornamentals. We examine the spatial distribution of ornamental alien plants in KNP, look at the link between human population size, history, and species richness, and show how the distribution of particular species reflects the likely history of ornamental plantings. Results are used to assess whether past management actions have been appropriately directed. Two hundred and fifty-eight alien species have been recorded in the 36 tourist camps and staff villages. The number of staff housed in villages explains much of the diversity of cultivated alien plant species. Older camps also tend to have more ornamental alien plant species. However, the lack of a strong link between camp age and number of cultivated species suggests that ornamental plants have been widely spread around the KNP by humans. We also show that increased camp activity (either size or age) has led to more ornamental species, while, with the notable exception of Skukuza, camp activity has had a much smaller effect on the number of noncultivated species. Noncultivated species tend to be naturally dispersed, as opposed to directly spread by humans between camps. Past management prioritized certain species on the basis of their potential to invade KNP and on the prevailing national legislation. These species were removed manually and follow-up control was carried out. Once the priority species were deemed to be under control, less invasive species were targeted. All alien species were removed from vacated houses, regardless of the potential invasiveness of the species. Electronic supplementary material The online version of this article (doi:) contains supplementary material, which is available to authorized users.     

Geochemistry and toxicity of sediment porewater in a salt-impacted urban stormwater detention pond

A comprehensive study was carried out to investigate the impacts of road salts on the benthic compartment of a small urban detention facility, Rouge River Pond. Although the pond is an engineered water body, it is representative of many small urban lakes, ponds and wetlands, which receive road runoff and are probable high impact areas. Specific objectives of the study were to document the porewater chemistry of an aquatic system affected by elevated salt concentrations and to carry out a toxicological assessment of sediment porewater to determine what factors may cause porewater toxicity. The results indicate that the sediment porewater may itself attain high salt concentrations. The computations show that increased chloride levels have important implications on the Cd complexation, augmenting its concentration in porewater. The toxicity tests suggest that the toxicity in porewater is caused by metals or other toxic chemicals, rather than high levels of chloride.     

The Probability of a Horizontal Gene Transfer from Roundup Ready® Soybean to Root Symbiotic Bacteria: A Risk Assessment Study on the GSF Lysimeter Station

The gene transfer from glyphosate tolerant soybean to Bradyrhizobium japonicum was evaluated in a free-air lysimeter experiment under natural conditions and increasing selection pressure, to monitor for the probability of horizontal gene transfer (HGT). A large volume lysimeter study that offers conditions comparable to normal farming was conducted in 2004 and 2005 with Roundup Ready® (RR) soybean and Roundup® application according to agricultural practice. Analysis of nodules showed, as expected, the presence of the transgenic 5-enolpyruvylshikimate-3-phosphate synthase (EPSPS). However, in bacteroids that were isolated from nodules and then cultivated for several rounds in the presence of high levels of glyphosate, the EPSPS gene could no longer be detected. This indicates no stable HGT transfer of the whole EPSPS gene under field conditions.     

Historical trends in persistent organic pollutants and metals recorded in sediment from Lake Ellasjøen, Bjørnøya, Norwegian Arctic

Ellasj?en receives contaminants from both atmospheric and biological transport (seabird guano). Historical trends of selected persistent organic pollutants and metals were determined by interpretation of down-core contaminant profiles in conjunction with sediment layer ages, determined by the (210)Pb method. Polychlorinated biphenyls (PCBs) and dichloro-diphenyl-trichloroethane and metabolites (DDTs) increased from about 1930 until 1970 (max. sum PCBs 71.8 ng/g dry weight (dw), max sum DDTs 4.0 ng/g dw), declining afterwards to 46.4 ng/g dw and 1.6 ng/g dw, respectively. Polybrominated diphenylethers (PBDEs) concentrations are increasing in Ellasj?en, reaching 0.73 ng/g dw in 2001. Hexabromocyclododekane (HBCD) was measured only in sediment from 1-2 cm depth (0.43 and 3.88 ng/g dw of alpha- and gamma-HBCD, respectively). Most metals (As, Cd, Co, Ni and Zn) showed a similar pattern as PCBs. No clear trends were observed for Cr, Pb or V. Mercury (Hg) has increased gradually since the beginning of the industrial era.     

Chronic toxicity of arsenic, cobalt, chromium and manganese to Hyalella azteca in relation to exposure and bioaccumulation

Chronic toxicity of As, Co, Cr and Mn to Hyalella azteca can be described using a saturation-based mortality model relative to total-body or water metal concentration. LBC25s (total-body metal concentrations resulting in 25% mortality in 4 weeks) were 125, 103, 152 and 57,900 nmol g-1 dry weight for As, Co, Cr and Mn respectively. LC50s (metal concentrations in water resulting in 25% mortality in 4 weeks) were 5600, 183, 731, and 197,000 nmol L-1, respectively. A hormesis growth response to As exposure was observed. Growth was a more variable endpoint than mortality for all four toxicants; however, confidence limits based on growth and mortality all overlapped, except Cr which had no effect on growth. Mn toxicity was greater in glass test containers compared to plastic. Bioaccumulation of As, Co, Cr, and Mn was strongly correlated with, and is useful for predicting, chronic mortality.