Human milk samples (n = 206) collected in 2014 from Belgian primiparous mothers were analyzed for seven groups of persistent organic pollutants (POPs): dichlorodiphenyltrichloroethane and its metabolites (DDTs), chlordane compounds (CHLs), hexachlorocyclohexane isomers (HCHs), hexachlorobenzene (HCB), polybrominated diphenyl ethers (PBDEs), pentachlorobenzene (PeCB), and hexabromobiphenyl (BB-153). Pooled samples for the analysis of hexachlorobutadiene, heptachlor, chlordecone, dieldrin, and hexabromocyclododecane (HBCD) were prepared. DDTs [median: 41 ng/g lipid weight (lw)], HCB (5.5 ng/g lw), and HCHs (2.4 ng/g lw) were the predominant compounds in all samples. Median levels of PBDEs (0.91 ng/g lw) in Belgian human breast milk samples were lower compared to other European countries. The major PBDE congeners were BDE-47 and BDE-153, and total PBDE levels were low (0.30-4.25 ng/g lw). α-HBCD was the only HBCD stereoisomer found in the pooled milk samples (2.5 ng/g lw). All targeted POPs were determined in a national pooled sample but were lower than levels of most POPs [organochlorine pesticides (OCPs), PBDEs, and polychlorinated biphenyls (PCBs)] observed in 2006. The daily dietary intake of POPs via human milk was estimated for nursing infants of 1 month [intake of 260 mL milk/kg body weight (bw)] and compared with either health-based guidance values (HBGV) or the reference point (margin of exposure, MOE). The exposure assessment in a worst-case scenario revealed no concern for most POPs. However, the infants were exposed to levels of 60 pg total WHO2005-TEQ/kg bw/week, indicating a possible risk during their life. Based on the MOE approach, 95th percentile of concentration can result in a health concern for congeners BDE-99 and BDE-153.

Microplastics (MPs) and nanoplastics have gained significant attention as emerging environmental pollutants due to their widespread presence and potential health risks. In recent years, these contaminants have been frequently detected in drinking water and various beverages, prompting concern about their sources and effects. This paper provides a comprehensive review of the occurrence of MPs in drinking water and beverages and exposure assessments. MP concentrations in drinking water vary significantly across countries and regions, influenced by diverse factors such as the efficiency of water treatment plants, the level of pollution in water sources, and the condition of transportation pipelines. Another critical aspect discussed in this review is the assessment of human exposure to MPs. Similarly, the daily intake of MPs shows significant variation across different countries and regions. Beyond the concentration of MPs in drinking water, an equally important factor is the quantity of water consumed, which can differ by as much as two orders of magnitude between studies. These variations in water consumption are a key focus of this article, as they greatly influence the estimation of human MP exposure. Furthermore, it discusses the limitations of current research, emphasizes gaps in understanding nanoplastics, and outlines potential future research directions.

The risk of developing chronic kidney disease (CKD), signified by a decrease in the estimated glomerular filtration rate (eGFR), has been linked to long-term exposure to low levels of the metal pollutant cadmium (Cd). Proteinuria is a hallmark of CKD and predicts continued progressive functional decline of the kidney. The aim of this study was to use the extent of proteinuria for Cd health risk assessment. Data were from 405 apparently healthy Thai nationals, of whom 12.6% had an eGFR below 60 mL/min/1.73 m² (low eGFR), and 16.3% and 13.5% had moderate and severe proteinuria. Urinary excretion of Cd (E_Cd) and urinary total protein (E_pro) were measured and normalized to both creatinine clearance (C_cr) and creatinine excretion (E_cr). We found that the risk of having a low eGFR [prevalence odds ratio (POR) = 12.2, P < 0.001] and severe proteinuria [POR = 10.4, P = 0.001) were increased markedly for every ten-fold increase in E_Cd/C_cr. However, when E_Cd was normalized to E_cr, the association between eGFR and E_Cd was found to be insignificant due to non-differential errors introduced by the E_cr-normalization. Respective benchmark dose limit (BMDL) values of E_Cd/E_cr that increased protein excretion by 5% and 10% were 0.0536 and 0.1140 µg/g creatinine. The E_Cd/E_cr at which 5% of the population had Cd-related proteinuria was 1.86 µg/g creatinine, respectively. For the first time, a urinary Cd excretion rate of 0.0536 µg/g creatinine has been derived as a Cd exposure level that produces negligible kidney damage.

Elevated levels of trace elements are thought to pose a serious health risk to workers in e-waste recycling facilities. We evaluated the distribution, contamination, and human health risks of trace elements in soil and dust from e-waste exposed and non-exposed sites in Bangladesh. Thirty-one soil (20 exposed; 11 non-exposed) and 31 dust samples (21 exposed; 10 non-exposed) were collected and analyzed for Pb, Cd, Hg, As, Cr, Cu, Mn, Ni, Zn, Be, Co, Se, and V using ICP-MS. The mean concentrations of Pb, Hg, Cu, and Zn concentrations were significantly higher in soil (587, 25.57, 2,912, 894 mg/kg) and dust (439, 59, 617, 1,201 mg/kg) than in non-exposed soil (15.94, 0.07, 23.71, 121 mg/kg; all P: ≤ 0.001) and dust (15, 3.56, 19, 213 mg/kg; all P: ≤ 0.001). Children were more vulnerable than adults to non-carcinogenic risks from ingestion, while non-carcinogenic risks from dermal and inhalation exposure were negligible. Pb, Hg, and Cu from soil, as well as Pb, Hg, and Cr from dust, showed a hazard index (HI) greater than 1, indicating a risk higher than the acceptable level for children and adults at the exposed sites, while the risk to a reference child and adults was negligible. Cr and Ni contributed to cancer risk only when their concentrations reached their maximum level, exceeding the permissible limit of 1 × 10^-4. This study demonstrates a significant accumulation of trace elements in e-waste recycling sites, where exposure through soil and dust poses environmental and human health risks, particularly for children. This underscores an urgent need for regulatory authorities to implement control measures and deploy awareness programs to limit trace element pollution and mitigate its impacts on the environment and human health.

The increasing number of motor vehicles due to economic and urbanization development has raised concerns about the impact of traffic-related air pollution on human health. Research on the impact of traffic-related pollution on populations, particularly in individuals with liver cirrhosis, is currently lacking. In this study, we utilized data from compensated cirrhosis patients at the Second People’s Hospital in Tianjin, China, to investigate the effects of traffic-related air pollution exposure on liver function-related blood indicators. A multiple linear regression model was applied to analyze the exposure to six air pollutants as well as the proximity of patients’ residential (or work) addresses to traffic arteries (main roads, secondary roads, highways). The results indicated a significant correlation between traffic-related air pollution and certain levels of liver function. Specifically, PM_2.5 exposure was positively correlated with prothrombin time [PT, P < 0.05, 95%CI = (0.119, 0.424)] and international normalized ratio [INR, P < 0.05, 95%CI = (0.003, 0.041)]; SO₂ exposure was positively correlated with cholesterol [CHO, P < 0.05, 95%CI = (0.126, 0.947)]; CO exposure was positively correlated with cholinesterase [CHE, P < 0.05, 95%CI = (15,276.644, 55,907.446)], triglyceride [TG, P < 0.05, 95%CI = (0.741, 7.215)], and hemoglobin [Hb, P < 0.05, 95%CI = (26.211, 305.697)]; O₃ exposure was positively correlated with creatine kinase [CK, P < 0.05, 95%CI = (0.012, 0.126)], CHO [P < 0.05, 95%CI = (0.008, 0.248)], and INR [P < 0.05, 95%CI = (0.001, 0.02)]; the distance to main roads was negatively correlated with aspartate aminotransferase [AST, P < 0.05, 95%CI = (-0.041, -0.001)], gamma-glutamyl transferase [GGT, P < 0.05, 95%CI = (-0.041, -0.001)], and serum ferritin [SF, P < 0.05, 95%CI = (-0.348, -0.062)]; and the distance to secondary roads was negatively correlated with PT [P < 0.05, 95%CI = (-0.007, -0.001)]. High-intensity traffic-related air pollution was found to have a negative influence on liver function, potentially causing liver damage. This research provides evidence of the detrimental effects of traffic-related air pollution on the liver.

Thirdhand smoke (THS) is the toxic residue left behind by tobacco smoke that persists indoors on carpets, furniture, toys, and other items. Children are especially vulnerable to THS exposure due to their hand-to-mouth behaviors, activity near the floor, and developing organs. We provide a scoping narrative review of potential sociodemographic disparities in exposure to THS among children in the United States. Articles were obtained by conducting a search in the PubMed, SCOPUS, and CINAHL databases. Other relevant papers were also reviewed and integrated using narrative synthesis. Studies relevant to THS exposure among 0 to 17-year-olds and conducted in the United States were included. We identified lower socioeconomic status (SES), race, younger age (2-4 years), and living in multiunit housing (MUH) as potential contributors to higher THS exposure risk in children. Lower income was associated with greater THS exposure. THS exposure was higher in Black children, although the number of studies involving them was limited. Examining disparities in exposure and susceptibility to THS can inform future policies to reduce children’s environmental exposure to toxic tobacco chemicals in THS. Housing type is likely a primary contributor to exposure disparities, as low-income children are more likely to live in multiunit, rented housing, where tobacco smoke can travel across housing units and where THS residue from former tenants can persist. Policies limiting persistent THS residue indoors through comprehensive smoking bans and expanded outreach on approaches to reduce THS exposures among children are needed.

Personal care products (PCPs), including skin lotions, toners, and make-up waters, are ubiquitous in daily life. Prior research has demonstrated hormesis, a biphasic dose-response phenomenon, in these PCPs on the freshwater photobacterium Vibrio qinghaiensis sp. -Q67 (Q67). Given that PCPs contain various active chemical components, their hormetic effects are intricately linked to these ingredients. However, studies focusing on the concentration-response relationships of individual PCP chemical ingredients are scarce. Building upon our previous work, we analyzed the ingredients of 6 PCPs and employed Q67 as a model organism to investigate the concentration-response relationships of these ingredients. Our analysis of 6 representative PCPs revealed 49 chemical ingredients, categorized into 10 moisturizers, 5 preservatives, 5 emulsifiers, 5 emollients, 20 ingredients with known efficacy, and 4 with unknown efficacy. Among these 49 chemical ingredients, 30 water-soluble ones were suitable for toxicity testing. At 0.25 h, 23 chemical ingredients exhibited S-shaped concentration-response curves (CRCs) with EC₅₀ values spanning from 6.943E-5 g/mL [lactic acid (LAA)] to 1.032 g/mL [sorbitol (SBO)], while 2 [PEG-7 glyceryl cocoate (PGC) and Tween 80 (TW80)] showed hormesis with J-shaped CRCs, and 5 [adenosine (ADE), dexpanthenol (DEX), E4C, E6C, serine (SER)] lacked discernible CRCs. At 12 h, 13 chemical ingredients displayed S-shaped CRCs with EC₅₀ values ranging from 4.402E-5 g/mL (E6C) to 1.961E-1 g/mL [dicaprylyl carbonate (DIC)], while 16 showed J-shaped CRCs, with EC₅₀, zero effective concentration point (ZEP), EC_min, and E_min values indicating a consistent variation range spanning 4 orders of magnitude. These findings underscore the importance of considering individual chemical ingredients in assessing the risks associated with PCPs.