Fate of phthalic acid esters during composting of both lagooning and activated sludges

Among the phthalic acid esters (PAEs) targeted by the United States Environmental Protection Agency (USEPA) as priority pollutants, di-ethyl-hexyl phthalate (DEHP) is the major pollutant identified at high concentration level in lagooning sludge (LS), at about 28.67 mg/kg, andin activated sludge (AS), at about 6.26 mg/kg. Other phthalic acid esters, such as di-butyl phthalate (DBP) and di-methyl phthalate (DMP) show very low concentrations. During sludge composting, after the stabilization phase, the subsequent appearance of DEP and then DMPoccurred indicating that microbial metabolism begins by alkyl side-chain degradation before aromatic ring-cleavage. The appearance andaccumulation of PAEs with a short alkyl side-chain in the last stages of AS and LS composting is suggested originating from the degradationof phthalates with a much long side-chain. The DEHP showed a rate of biodegradation that follows a first-order kinetic model during composting of both AS and LS. The calculated DEHP half-lives are 45.4 days for LS and 28.9 days for AS. The better DEHP biodegradationrate (2.4 Â 10À2 dayÀ1) have been observed in the case of AS composting compared to LS compost (1.53 Â 10À2 dayÀ1). The mono-ethyl-hexyl phthalates MEHP has been shown to follow the same order of biodegradation as DEHP indicating that the same mechanism is followed(hydrolysis or dealkylation of each DEHP side-chain). Composting could be suggested as a detoxification process for the removal of PAEs(mainly DEHP) from sludges after a sufficient time of treatment to provide a safe end product

Development and validation of methods for the trace determination of phthalates in sludge and vegetables

A routine method which is simple, quick and precise has been set up and validated for phthalate analysis in environmental samples (tomato plants and sewage sludges). Six phthalates have been studied simultaneously: dimethylphthalate, diethylphthalate, dibutylphthalate, butylbenzylphthalate, di(ethyl)hexylphthalate and dioctylphthalate. Optimization of sample, solvent extraction uses a Soxtec apparatus and extract purification with an SPE cartridge allows between 90 to 110 % recovery of phthalates. Precise, sensitive and selective identification and quantifying of analytes is by GC-MS in SIM mode. This protocol allows analytes with concentrations as low as 10µg/kg Dry Matter (DM) to be determined from small (1 to 2 g DM) samples. This analytical method has been applied to the phthalate transfer study for agricultural recycling of sludges, where phthalate bioavailability has been studied in aquiculture using two types of experiments. Tomatoes have been grown in containers where the trace organics have been directly introduced as pure substances, and in a second experiment under the same growth conditions, sewage sludge has replaced the pure substances. Transfer of these trace organics has been followed into the various parts of the tomato plant and in general only the DEHP is worthy of note although its percentage transfer remains very low even in an experiment designed to maximize this

Association of Prenatal Urinary Concentrations of Phthalates and Bisphenol A and Pubertal Timing in Boys and Girls.

BackgroundAnimal studies suggest that phthalates and bisphenol A (BPA), endocrine-disrupting chemicals found in many consumer products, may impact the timing of puberty.ObjectivesWe aimed to determine the association of prenatal exposure to high-molecular-weight phthalates and BPA with pubertal timing in boys and girls participating in the Center for the Health Assessment of Mothers and Children of Salinas (CHAMACOS) longitudinal cohort study.MethodsWe quantified urinary concentrations of eight phthalate metabolites and BPA at two time points during pregnancy among participating mothers ([Formula: see text]) and conducted clinical Tanner staging of puberty on their children every 9 months between 9 and 13 y of age. We conducted accelerated failure time models and examined the role of child overweight/obese status in this association.ResultsThe sum of urinary metabolites of di(2-ethylhexyl) phthalate [Formula: see text], monobenzyl phthalate (MBzP), and BPA were associated with later onset of at least one of the three outcomes assessed in girls (thelarche, pubarche, or menarche) and with earlier onset of at least one of the two outcomes assessed in boys (gondarche and pubarche). We found that monocarboxynonyl phthalate, monocarboxyoctyl phthalate, mono(3-carboxypropyl) phthalate, and BPA were associated with later pubarche and menarche mostly among normal-weight girls but not overweight/obese girls. MBzP was associated with later thelarche in all girls, and [Formula: see text] was associated with later thelarche and menarche in all girls. BPA and all phthalate biomarkers were associated with earlier gonadarche and pubarche in all boys as well as in overweight/obese boys when stratified by weight. Among normal-weight boys, associations with BPA were also inverse, whereas associations with phthalate metabolites were close to the null or positive.ConclusionsSeveral high-molecular-weight phthalates and BPA were associated with later puberty in girls and earlier puberty in boys included in the CHAMACOS cohort study. Childhood overweight/obesity may modify these associations. https://doi.org/10.1289/EHP3424

A method validation for simultaneous determination of phthalates and bisphenol A released from plastic water containers

Phthalates (or phthalate esters, PAEs) and bisphenol A (BPA) are widely used in various industries, particularly in the fields of cosmetics and packaging, and they increase the malleability and workability of materials. As a result of their use, some international health organizations have begun to study them. In this study, the authors developed a methodology for the simultaneous determination of dimethyl phthalate (DMP), diethyl phthalate (DEP), diisobutyl phthalate (DiBP); dibutyl phthalate (DBP), bis(2-ethylhexyl) phthalate (DEHP); di-n-octyl-phthalate (DnOP) and bisphenol A (BPA) from drinking and non-potable waters. The extraction of PAEs and BPA was performed using a solvent-based dispersive liquid-liquid microextraction (SB-DLLME) method. The analytical determination was performed using a gas chromatography-ion trap mass spectrometry (GC-IT/MS) analysis. The entire procedure was validated as recoveries were studied according to the volume and the extraction solvent used, pH, and ionic strength. Dynamic linearity ranges and linear equations of all the compounds were experimentally determined as well as the limit of detection (LOD) (1-8 ng mL-1) and the limit of quantification (LOQ) (5-14 ng mL-1), reproducibility, and sensitivity. The method was applied to 15 water samples (mineral water and tap water) for determining PAEs and BPA released from the plastic container. After the release simulation, four PAEs (i.e., DiBP, DBP, DHEP, and DnOP) were determined at very low concentrations (below 1.2 ng mL-1) in two water samples from (sport) bottles

Synergistic disruption of external male sex organ development by a mixture of four antiandrogens

Reproduced with permission from Environmental Health Perspectives.Background: By disrupting the action of androgens during gestation, certain chemicals present in food, consumer products, and the environment can induce irreversible demasculinization and malformations of sex organs among male offspring. However, the consequences of simultaneous exposure to such chemicals are not well described, especially when they exert their actions by differing molecular mechanisms. Objectives: To fill this gap, we investigated the effects of mixtures of a widely used plasticizer, di(2-ethylhexyl) phthalate (DEHP); two fungicides present in food, vinclozolin and prochloraz; and a pharmaceutical, finasteride, on landmarks of male sexual development in the rat, including changes in anogenital distance (AGD), retained nipples, sex organ weights, and malformations of genitalia. These chemicals were chosen because they disrupt androgen action with differing mechanisms of action. Results: Strikingly, the effect of combined exposure to the selected chemicals on malformations of external sex organs was synergistic, and the observed responses were greater than would be predicted from the toxicities of the individual chemicals. In relation to other hallmarks of disrupted male sexual development, including changes in AGD, retained nipples, and sex organ weights, the combined effects were dose additive. When the four chemicals were combined at doses equal to no observed adverse effect levels estimated for nipple retention, significant reductions in AGD were observed in male offspring. Conclusions: Because unhindered androgen action is essential for human male development in fetal life, these findings are highly relevant to human risk assessment. Evaluations that ignore the possibility of combination effects may lead to considerable underestimations of risks associated with exposures to chemicals that disrupt male sexual differentiation.European Union and the Danish Environmental Protection Agency

Estimated daily phthalate exposures in a population of mothers of male infants exhibiting reduced anogenital distance.

Phthalate diesters have been shown to be developmental and reproductive toxicants in animal studies. A recent epidemiologic study showed certain phthalates to be significantly associated with reduced anogenital distance in human male infants, the first evidence of subtle developmental effects in human male infants exposed prenatally to phthalates. We used two previously published methods to estimate the daily phthalate exposures for the four phthalates whose urinary metabolites were statistically significantly associated with developmental effects in the 214 mother-infant pairs [di-n-butyl phthalate (DnBP) , diethyl phthalate (DEP) , butylbenzyl phthalate (BBzP) , diisobutyl phthalate (DiBP) ] and for another important phthalate [di-2-ethylhexyl phthalate (DEHP) ]. We estimated the median and 95th percentile of daily exposures to DBP to be 0.99 and 2.68 microg/kg/day, respectively ; for DEP, 6.64 and 112.3 microg/kg/day ; for BBzP, 0.50 and 2.47 microg/kg/day ; and for DEHP, 1.32 and 9.32 microg/kg/day. The U.S. Environmental Protection Agency (EPA) reference doses for these chemicals are 100 (DBP) , 800 (DEP) , 200 (BBzP) , and 20 (DEHP) microg/kg/day. The median and 95th percentile exposure estimates for the phthalates associated with reduced anogenital distance in the study population are substantially lower than current U.S. EPA reference doses for these chemicals and could be informative to any updates of the hazard assessments and risk assessments for these chemicals

Plasticizer degradation by marine bacterial isolates : a proteogenomic and metabolomic characterization

Many commercial plasticizers are toxic endocrine-disrupting chemicals that are added to plastics during manufacturing and may leach out once they reach the environment. Traditional phthalic acid ester plasticizers (PAEs), such as dibutyl phthalate (DBP) and bis(2-ethyl hexyl) phthalate (DEHP), are now increasingly being replaced with more environmentally friendly alternatives, such as acetyl tributyl citrate (ATBC). While the metabolic pathways for PAE degradation have been established in the terrestrial environment, to our knowledge, the mechanisms for ATBC biodegradation have not been identified previously and plasticizer degradation in the marine environment remains underexplored. From marine plastic debris, we enriched and isolated microbes able to grow using a range of plasticizers and, for the first time, identified the pathways used by two phylogenetically distinct bacteria to degrade three different plasticizers (i.e., DBP, DEHP, and ATBC) via a comprehensive proteogenomic and metabolomic approach. This integrated multi-OMIC study also revealed the different mechanisms used for ester side-chain removal from the different plasticizers (esterases and enzymes involved in the β-oxidation pathway) as well as the molecular response to deal with toxic intermediates, that is, phthalate, and the lower biodegrading potential detected for ATBC than for PAE plasticizers. This study highlights the metabolic potential that exists in the biofilms that colonize plastics-the Plastisphere-to effectively biodegrade plastic additives and flags the inherent importance of microbes in reducing plastic toxicity in the environment

Does home cooking have an effect on phthalate levels in food?

A

Urinary Phthalate Metabolites and Biomarkers of Oxidative Stress in a Mexican-American Cohort: Variability in Early and Late Pregnancy.

People are exposed to phthalates through their wide use as plasticizers and in personal care products. Many phthalates are endocrine disruptors and have been associated with adverse health outcomes. However, knowledge gaps exist in understanding the molecular mechanisms associated with the effects of exposure in early and late pregnancy. In this study, we examined the relationship of eleven urinary phthalate metabolites with isoprostane, an established marker of oxidative stress, among pregnant Mexican-American women from an agricultural cohort. Isoprostane levels were on average 20% higher at 26 weeks than at 13 weeks of pregnancy. Urinary phthalate metabolite concentrations suggested relatively consistent phthalate exposures over pregnancy. The relationship between phthalate metabolite concentrations and isoprostane levels was significant for the sum of di-2-ethylhexyl phthalate and the sum of high molecular weight metabolites with the exception of monobenzyl phthalate, which was not associated with oxidative stress at either time point. In contrast, low molecular weight metabolite concentrations were not associated with isoprostane at 13 weeks, but this relationship became stronger later in pregnancy (p-value = 0.009 for the sum of low molecular weight metabolites). Our findings suggest that prenatal exposure to phthalates may influence oxidative stress, which is consistent with their relationship with obesity and other adverse health outcomes