Category Archives: Environ Int

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Prenatal exposure to persistent organic pollutants and cognition and motor performance in adolescence.

Environ Int. 2018 Aug 29;121(Pt 1):13-22

Authors: Berghuis SA, Van Braeckel KNJA, Sauer PJJ, Bos AF

Abstract
BACKGROUND: Prenatal exposure to persistent organic pollutants (POPs), such as polychlorinated biphenyls (PCBs), was found to be associated with poorer neurological development in children. Knowledge about the effects on outcomes until adolescence is limited.
OBJECTIVES: To determine whether prenatal exposure to POPs, particularly hydroxylated PCBs (OH-PCBs), is associated with cognitive and motor development in 13- to 15-year-old children.
METHODS: This prospective observational cohort study is part of the Development at Adolescence and Chemical Exposure (DACE)-study, a follow-up of two Dutch birth cohorts. Maternal pregnancy serum levels of PCB-153 and three OH-PCBs were measured, in part of the cohort also nine other PCBs and three OH-PCBs, and in another part five polybrominated diphenyl ethers (PBDEs), dichloroethene (DDE), pentachlorophenol (PCP) and hexabroomcyclododecane (HBCDD). Of the 188 invited adolescents, 101 (53.7%) participated, 55 were boys. Cognition (intelligence, attention, verbal memory) and motor performance (fine motor, ball skills, balance) were assessed. Scores were classified into ‘normal’ (IQ > 85; scores > P15) and ‘(sub)clinical’ (IQ ≤ 85; scores ≤ P15). We used linear and logistic regression analyses, and adjusted for maternal education, maternal smoking, maternal alcohol use, breast feeding, and age at examination.
RESULTS: Several OH-PCBs were associated with more optimal sustained attention and balance. PCB-183 was associated with lower total intelligence (OR: 1.29; 95%CI:0.99-1.68; P = .060), and HBCDD with lower performance intelligence (OR: 3.62; 95%CI:0.97-13.49; P = .056). PCBs, OH-PCBs and PBDEs were negatively associated with verbal memory.
CONCLUSIONS: Prenatal background exposure to several POPs can influence neuropsychological outcomes in 13- to 15-year-old Dutch adolescents, although exposure to most compounds does not have clinically relevant consequences at adolescence.

PMID: 30172231 [PubMed – as supplied by publisher]

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Toxicological risk assessment and prioritization of drinking water relevant contaminants of emerging concern.

Environ Int. 2018 Jun 13;118:293-303

Authors: Baken KA, Sjerps RMA, Schriks M, van Wezel AP

Abstract
Toxicological risk assessment of contaminants of emerging concern (CEC) in (sources of) drinking water is required to identify potential health risks and prioritize chemicals for abatement or monitoring. In such assessments, concentrations of chemicals in drinking water or sources are compared to either (i) health-based (statutory) drinking water guideline values, (ii) provisional guideline values based on recent toxicity data in absence of drinking water guidelines, or (iii) generic drinking water target values in absence of toxicity data. Here, we performed a toxicological risk assessment for 163 CEC that were selected as relevant for drinking water. This relevance was based on their presence in drinking water and/or groundwater and surface water sources in downstream parts of the Rhine and Meuse, in combination with concentration levels and physicochemical properties. Statutory and provisional drinking water guideline values could be derived from publically available toxicological information for 142 of the CEC. Based on measured concentrations it was concluded that the majority of substances do not occur in concentrations which individually pose an appreciable human health risk. A health concern could however not be excluded for vinylchloride, trichloroethene, bromodichloromethane, aniline, phenol, 2-chlorobenzenamine, mevinphos, 1,4-dioxane, and nitrolotriacetic acid. For part of the selected substances, toxicological risk assessment for drinking water could not be performed since either toxicity data (hazard) or drinking water concentrations (exposure) were lacking. In absence of toxicity data, the Threshold of Toxicological Concern (TTC) approach can be applied for screening level risk assessment. The toxicological information on the selected substances was used to evaluate whether drinking water target values based on existing TTC levels are sufficiently protective for drinking water relevant CEC. Generic drinking water target levels of 37 μg/L for Cramer class I substances and 4 μg/L for Cramer class III substances in drinking water were derived based on these CEC. These levels are in line with previously reported generic drinking water target levels based on original TTC values and are shown to be protective for health effects of the majority of contaminants of emerging concern evaluated in the present study. Since the human health impact of many chemicals appearing in the water cycle has been studied insufficiently, generic drinking water target levels are useful for early warning and prioritization of CEC with unknown toxicity in drinking water and its sources for future monitoring.

PMID: 29909348 [PubMed – as supplied by publisher]

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Trigger values for investigation of hormonal activity in drinking water and its sources using CALUX bioassays.

Environ Int. 2013 Mar 27;55C:109-118

Authors: Brand W, de Jongh CM, van der Linden SC, Mennes W, Puijker LM, van Leeuwen CJ, van Wezel AP, Schriks M, Heringa MB

Abstract
To screen for hormonal activity in water samples, highly sensitive in vitro CALUX bioassays are available which allow detection of estrogenic (ERα), androgenic (AR), progestagenic (PR), and glucocorticoid (GR) activities. This paper presents trigger values for the ERα, AR, PR, and GR CALUX bioassays for agonistic hormonal activities in (drinking) water, which define a level above which human health risk cannot be waived a priori and additional examination of specific endocrine activity may be warranted. The trigger values are based on 1) acceptable or tolerable daily intake (ADI/TDI) values of specific compounds, 2) pharmacokinetic factors defining their bioavailability, 3) estimations of the bioavailability of unknown compounds with equivalent hormonal activity, 4) relative endocrine potencies, and 5) physiological, and drinking water allocation factors. As a result, trigger values of 3.8ng 17β-estradiol (E2)-equivalents (eq)/L, 11ng dihydrotestosterone (DHT)-eq/L, 21ng dexamethasone (DEX)-eq/L, and 333ng Org2058-eq/L were derived. Benchmark Quotient (BQ) values were derived by dividing hormonal activity in water samples by the derived trigger using the highest concentrations detected in a recent, limited screening of Dutch water samples, and were in the order of (value) AR (0.41)>ERα (0.13)>GR (0.06)>PR (0.04). The application of trigger values derived in the present study can help to judge measured agonistic hormonal activities in water samples using the CALUX bioassays and help to decide whether further examination of specific endocrine activity followed by a subsequent safety evaluation may be warranted, or whether concentrations of such activity are of low priority with respect to health concerns in the human population. For instance, at one specific drinking water production site ERα and AR (but no GR and PR) activities were detected in drinking water, however, these levels are at least a factor 83 smaller than the respective trigger values, and therefore no human health risks are to be expected from hormonal activity in Dutch drinking water from this site.

PMID: 23542573 [PubMed – as supplied by publisher]

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