The ubiquitous exposure of humans to microplastics (MPs) through inhalation of particles in air and ingestion in dust, water, and diet is well established. Humans are estimated to ingest tens of ...thousands to millions of MP particles annually, or on the order of several milligrams daily. Available information suggests that inhalation of indoor air and ingestion of drinking water bottled in plastic are the major sources of MP exposure. Little is known on the occurrence of MPs in human diet. Evidence is accumulating that feeding bottles and medical devices can contribute to MP exposure in newborns and infants. Biomonitoring studies of human stool, fetus, and placenta provide direct evidence of MP exposure in infants and children. MPs <20 µm were reported to cross biological membranes. Although plastics were once perceived as inert materials, MP exposure in laboratory animals is linked to various forms of inflammation, immunological response, endocrine disruption, alteration of lipid and energy metabolism, and other disorders. Whereas exposure to MPs itself is a concern, MPs can also be sources of exposure to plastic additives and other toxicants. Exposure of human cell lines to MP additives such as phthalates, bisphenols, and organotins causes adverse effects through the activation of nuclear receptors, peroxisome proliferator-activated receptors (PPARs) α, β, and γ, and retinoid X receptor (RXR), leading to oxidative stress, cytotoxicity, immunotoxicity, thyroid hormone disruption, and altered adipogenesis and energy production. The size, shape, chemical composition, surface charge, and hydrophobicity of MPs influence their toxicity. Maternal transfer of MPs to the developing fetus has been demonstrated in exposed laboratory animals and through the analysis of human placenta. In laboratory animal studies, maternal exposure to MPs altered energy and lipid metabolism in offspring and subsequent generations. Moreover, concomitant with the global increase in plastics production, the prevalence of overweight and obesity in human populations has increased over the past five decades, and there is evidence to support the hypothesis that MPs and their additives are potential obesogens. Even though MP exposures are ubiquitous and toxic effects from such exposures are a concern, systematic studies on this topic remain urgently needed.
Despite the widespread usage of phthalates and parabens in personal care products (PCPs), little is known about concentrations and profiles as well as human exposure to these compounds through the ...use of PCPs. In this study, nine phthalates and six parabens were determined in 170 PCPs (41 rinse-off and 109 leave-on), including 20 baby care products collected from Albany, New York. Phthalates were less frequently found in rinse-off PCPs but were more frequently found in perfumes (detection frequency of 100% for diethyl phthalate DEP, 67% for dibutyl phthalate DBP), skin toners (90% for DEP), and nail polishes (90% for DBP). Parabens were found in ∼40% of rinse-off products and ∼60% of leave-on products. The highest concentrations of DEP, DBP, methyl- (MeP), ethyl- (EtP), propyl- (PrP), and butyl parabens (BuP) were on the order of 1000 μg per gram of the product. On the basis of amount and frequency of use of PCPs and the measured median concentrations of target analytes, the total dermal intake doses (sum of all phthalates or parabens) were calculated to be 0.37 and 31.0 μg/kg-bw/day for phthalates and parabens, respectively, for adult females. The calculated dermal intake of phthalates from PCPs was lower for infants and toddlers than for adult females. In contrast, dermal intake of parabens from PCPs by infants and toddlers was higher than that for adult females. The calculated maximum daily exposure dose of MeP, EtP, and PrP from PCPs ranged between 58.6 and 766 μg/kg-bw/day for infants and toddlers, which was 3 times higher than that calculated for adult females. PCPs are an important source of human exposure to parabens; the contribution of PCPs to phthalate exposure is low, except for DEP.
Synthetic phenolic antioxidants (SPAs) such as 2,6-di-tert-butyl-4-hydroxytoluene (butylated hydroxytoluene, BHT), are used in a wide variety of consumer products, including certain foodstuffs (e.g. ...fats and oils) and cosmetics. Although BHT is considered generally safe as a food preservative when used at approved concentrations, there is debate whether BHT exposure is linked to cancer, asthma, and behavioral issues in children. Little is known with regard to human exposure to SPAs and the methods to measure these chemicals in urine. In this study, six SPAs and the metabolites were analyzed in 145 urine samples collected from four Asian countries (China, India, Japan, and Saudi Arabia) and the United States. BHT was found in 88% of the urine samples at median and maximum concentrations of 1.26 and 15 ng/mL, respectively. BHT metabolites and butylated hydroxyanisole (BHA) were found in 39% to 89% of the urine samples at a concentration range of <LOQ-46 ng/mL. 3,5-Di-tert-butyl-4-hydroxybenzoic acid (BHT-COOH), the major metabolite of BHT, is suggested as a potential urinary biomarker of exposure to BHT. The estimated median daily intakes (EDIs) of BHT, calculated from urinary concentrations, in children and adults were 0.38–56.6 and 0.21–31.3 μg/kg bw/day, respectively. BHT levels were high in urine samples from Japan, India, and the United States.
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•Synthetic phenolic antioxidants were measured in human urine for the first time.•3,5-di-tert-butyl-4-hydroxybenzoic acid is a biomarker of BHT in urine.•The highest BHT exposure was found in samples from Japan, India and the U.S.•Besides diet, several other sources contribute to BHT exposure.
Organophosphate esters (OPEs) are ubiquitous contaminants in the environment, but little is known about their occurrence in foodstuffs, an important source of human exposure. In this study, 15 OPEs ...were measured in foodstuffs and food-packing materials collected from local markets in Albany, New York, United States, for the first time. Among the foodstuffs analyzed, median concentrations of ∑OPEs (sum of 15 OPEs) in meat (6.76 ng/g wet weight; ww) and fish/seafood (7.11 ng/g ww) were higher than those in other food categories. ∑OPEs were found in food packaging at a median concentration of 132 ng/g. The estimated daily dietary intakes (EDIs) of OPE were of 37.9, 135, 56.6, 32.2, and 25.1 ng/kg body weight (bw)/day for infants, toddlers, children, teenagers, and adults, respectively. Meat was a major source (47%) of dietary OPEs exposure in adults, whereas dairy products accounted for 52% of OPE exposures in toddlers.
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•Neonicotinoids and dialkylphosphates were measured in urine from nine countries.•The highest sum concentration of 14 neonicotinoids was found in Vietnam (12.2 ng/mL).•The highest sum ...concentration of six dialkylphosphates was found in China (18.4 ng/mL).•Dimethyl phosphates accounted for 51–89% of the total concentrations.•Daily exposure dose to organophosphates was highest in China (515 μg/day).
The application of neonicotinoid insecticides (neonics) has increased dramatically as a replacement for organophosphate pesticides (OPs) in recent years. Nevertheless, little is known about human exposure to these pesticides in various countries. In this study, concentrations of 14 neonics and six dialkylphosphate metabolites (DAPs) were determined simultaneously in 566 urine samples collected from nine countries during 2010–2014. The highest sum concentration of 14 neonics was found in urine from Vietnam (median: 12.2 ng/mL) whereas that of six DAPs was from China (18.4 ng/mL). The median concentrations of ∑6 DAPs were twice higher than those of ∑14 neonics across the nine countries, which suggested a greater exposure to OPs than neonics. The overall pattern of urinary pesticide concentrations was similar among the nine countries with dimethylphosphate (DMP) and dimethylthiophosphate (DMTP) accounting for 51–89% of the total pesticide concentrations. Differences in urinary pesticide concentrations between genders (female and male), age groups (≤20, 21–49, and ≥50 years), and regions (cities of Shanghai, Guangzhou and Qiqihar) were examined. Total daily exposure doses to OPs were highest in China (515 μg/day) with 15% of the samples exceeding the U.S. Environmental Protection Agency’s reference dose for chlorpyrifos (18 μg/day). This is the first study to establish baseline levels of OP and neonics exposure in general populations across nine countries.
Little is known about the occurrence of emerging environmental contaminants, such as benzotriazoles (BTRs), benzothiazoles (BTHs), benzophenones (BzPs), and bisphenol analogues (BPs) in India. In ...this study, we determined the occurrence and removal of BTRs, BTHs, BzPs, and BPs in five Indian sewage treatment plants (STPs). The respective measured mean concentrations (N = 5) in influents and effluents were 370 and 57.4 ng L−1 for BTRs, 50800 and 20200 ng L−1 for BTHs, 351 and 163 ng L−1 for BzPs, and 98.0 and 9.6 ng L−1 for BPs. Among the target chemicals analyzed, BTHs were found at elevated levels, and the measured levels were some of the highest ever reported in the literature. The mean concentrations (N = 5) of BTRs, BTHs, BzPs, and BPs in sludge were 44.2, 51200, 124, and 200 ng g−1 dry wt, respectively. The removal efficiencies for BTRs, BTHs, BzPs, and BPs ranged as follows: 54.2–85.6%, 23.4–85.0%, 51.8–71%, and 76.0–97.0%, respectively, and were comparable to those reported for other countries. Elevated concentrations of BTHs in Indian STPs can be related to consumption of these chemicals in a wide range of products including paper, textile and rubber materials.
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•Mass loading and removal of 21 emerging contaminants were determined in Indian STPs.•BTHs were found at the highest concentration, at 49,400 ng L−1 in influents and 50,200 ng g−1, dry wt in sludge.•Select benzophenone derivatives were measured in STPs for the first time.•Removal efficiencies of the emerging chemicals in STPs ranged from 23.4 to 97%.
The fates of psychoactive pharmaceuticals, including two antischizophrenics, six sedative–hypnotic–anxiolytics, four antidepressants, four antihypertensives, and their select metabolites, were ...determined in two wastewater treatment plants (WWTPs) in the Albany area of New York. All target psychoactive pharmaceuticals and their metabolites were found at a mean concentration that ranged from 0.98 (quetiapine) to 1220ng/L (atenolol) in wastewater and from 0.26 (lorazepam) to 1490ng/g dry weight (sertraline) in sludge. In this study, the fraction of psychoactive pharmaceuticals that was sorbed to suspended particulate matter (SPM) was calculated for the first time. Over 50% of the total mass of aripiprazole, norquetiapine, norsertraline, citalopram, desmethyl citalopram, propranolol, verapamil, and norverapamil was found sorbed to SPM in the influent. The mass loadings, i.e., influx, of target psychoactive pharmaceuticals in WWTPs ranged from 0.91 (diazepam) to 347mg/d/1000 inhabitants (atenolol), whereas the environmental emissions ranged from 0.01 (dehydro-aripiprazole) to 316mg/d/1000 inhabitants (atenolol). The highest calculated removal efficiencies were found for antischizophrenics (quetiapine=88%; aripiprazole=71%). However, the removal of some psychoactive pharmaceuticals through adsorption onto sludge was minimal (<1% of the initial mass load), which suggests that bio-degradation and/or chemical-transformation are the dominant mechanisms of removal of these pharmaceuticals in WWTPs.
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•16 psychoactive pharmaceuticals were found at 0.98–1220ng/L in wastewater influent.•Over 50% of total mass of 8 psychoactives were found sorbed to particulate matter.•Influx of psychoactives in WWTPs ranged from 0.91 to 347mg/d/1000 inhabitants.•Environmental emission of psychoactives ranged from 0.01 to 316mg/d/1000 inhabitants.
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•PET and PC-based microplastics were detected in indoor dust from 12 countries.•High concentrations (38–120,000 µg/g) of PET-based MPs were found.•Positive correlations were found ...between monomers and corresponding MPs in dust.•The daily intake of MPs via indoor dust ingestion in infants was on the order of µg/kg bw.
Global marine pollution by microplastics (MPs) has received considerable attention in recent years. Nevertheless, little is known about the occurrence of MPs in indoor environments. A novel analytical method was used to quantitatively determine polyethylene terephthalate (PET)- and polycarbonate (PC)- based MPs in 286 indoor dust samples collected from 12 countries. PET-based MPs were detected in all dust samples at concentrations of 38–120,000 µg/g (median: 5900 µg/g), whereas PC-based MPs were measured at <0.11–1700 µg/g (median: 8.8 µg/g). Significant positive correlations were found between the concentrations of terephthalic acid (a PET monomer) and PET as well as between bisphenol A (a PC monomer) and PC. Based on the concentrations of MPs measured in indoor dust, the median daily intake of PET-based MPs calculated for infants was in the range of 4000–150,000 ng/kg-bw/day.
Bisphenol A (BPA) is used in a variety of consumer products, including some paper products, particularly thermal receipt papers, for which it is used as a color developer. Nevertheless, little is ...known about the magnitude of BPA contamination or human exposure to BPA as a result of contact with paper and paper products. In this study, concentrations of BPA were determined in 15 types of paper products (n = 202), including thermal receipts, flyers, magazines, tickets, mailing envelopes, newspapers, food contact papers, food cartons, airplane boarding passes, luggage tags, printing papers, business cards, napkins, paper towels, and toilet paper, collected from several cities in the USA. Thermal receipt papers also were collected from Japan, Korea, and Vietnam. BPA was found in 94% of thermal receipt papers (n = 103) at concentrations ranging from below the limit of quantitation (LOQ, 1 ng/g) to 13.9 mg/g (geometric mean: 0.211 mg/g). The majority (81%) of other paper products (n = 99) contained BPA at concentrations ranging from below the LOQ to 14.4 μg/g (geometric mean: 0.016 μg/g). Whereas thermal receipt papers contained the highest concentrations of BPA (milligram-per-gram), some paper products, including napkins and toilet paper, made from recycled papers contained microgram-per-gram concentrations of BPA. Contamination during the paper recycling process is a source of BPA in paper products. Daily intake (DI) of BPA through dermal absorption was estimated based on the measured BPA concentrations and handling frequency of paper products. The daily intake of BPA (calculated from median concentrations) through dermal absorption from handling of papers was 17.5 and 1300 ng/day for the general population and occupationally exposed individuals, respectively; these values are minor compared with exposure through diet. Among paper products, thermal receipt papers contributed to the majority (>98%) of the exposures.