Assessment of exposure to polybrominated diphenyl ethers associated with consumption of market hens in Guangzhou

Fetal exposure to organic contaminants revealed by infant hair: A preliminary study in south China

Fetal exposure to multiple organic contaminants (OCs) is a public concern because of the adverse effects of OCs on early life development. Infant hair has the potential to be used as an alternative matrix to identify susceptible fetuses, owing to its reliability, sensitivity, and advantages associated with sampling, handling, and ethics. However, the applicability of infant hair for assessing in utero exposure to OCs is still limited. In this study, 57 infant hair samples were collected in Guangzhou, South China, to evaluate the levels and compositions of typical OCs in the fetus. Most of the target OCs were detected in infant hair, with medians of 144 μg/g, 17.7 μg/g, 192 ng/g, 46.9 ng/g, and 1.36 ng/g for phthalate esters (PAEs), alternative plasticizers (APs), organophosphorus flame retardants (OPFRs), polybrominated diphenyl ethers (PBDEs), and organochlorine pesticides (OCPs), respectively. Meanwhile, paired maternal hair (0-9 cm from the scalp) was collected to examine the associations between maternal and infant hair for individual compounds. Low-brominated PBDEs tended to deposit in infant hair, with median concentrations approximately two times higher than those in maternal samples. Levels of PBDEs and 4,4'-dichlorodiphenyldichloroethylene (p,p'-DDE) in paired maternal and infant hair showed strong positive correlations (p < 0.05), while most plasticizers (PAEs and APs) were poorly correlated between paired hair samples. Exposure sources were responsible for the variation in correlation between OC levels in the paired infant and maternal samples. Crude relationships between fetal exposure to OCs and birth size were examined using the Bayesian kernel machine regression (BKMR) model. BDE-28 was found to be adversely associated with the birth size. This study provides referential information for evaluating in utero exposure to OCs and their health risks based on infant hair.

Pollution level, spatial distribution, and congener fractionation characteristics of low-brominated polybrominated diphenyl ethers (PBDEs) in sediments around Chaohu Lake, China

As new persistent organic compounds, polybrominated diphenyl ethers (PBDEs) have aroused important concern because of their potential bioaccumulation and possible ecological and health risk. To examine the sources and temporal variation of PBDEs in Chaohu Lake in eastern China, the surface sediments from Nanfei River (NFR) and core sediments from four estuaries were measured. It showed that low-brominated congeners were dominant, from MonoBDEs to HeptaBDEs (referred to as Σ₃₉PBDE). Concentrations of ∑₃₉PBDE and the ratios of (BDE-47 + BDE-99 + BDE-100)/(BDE-153 + BDE-154) were much greater in surface sediments than in core sediments. The highest concentration was observed in a site close to the outfall of a municipal sewage treatment plant (MSTP), and the ratio was significantly correlated with ∑₃₉PBDE. These results suggested that PentaBDE and OctaBDE commercial mixtures were widely used around Chaohu Lake and the effluent of municipal sewage was a dominant source of PBDEs to surface sediment. Compared to data from other freshwater systems around the world, the concentrations of BDE-47 and BDE-99 in this study were in the middle of the range of global data, but BDE-183 concentrations were at the high end of the range. Due to restrictions on the usage of PentanBDE and OctaBDE commercial mixtures, reductions of PBDE levels from subsurface to superficial layer were observed in all estuaries. Elevated contribution by MonoBDEs to ∑₃₉PBDE in the estuary of the only outflow river suggests significant congener fractionation. TriBDEs, TetraBDEs, and HexaBDEs appeared to pose low risks in all surface sediments, but moderate to high risks may be expected for PentaBDEs. Overall, the results would contribute to a better understanding of the sources and environmental fate of PBDEs in the studied eutrophicated lake.

Human exposure to polybrominated diphenyl ethers (PBDEs) through the diet: An update of the scientific literature

Polybrominated diphenyl ethers (PBDEs) are a class of brominated flame-retardants (BFRs). As for other persistent organic pollutants, dietary intake (followed by dust inhalation) is the main route of human exposure to PBDEs. In 2012, we reviewed the scientific literature on the concentrations of PBDEs in foodstuffs and their dietary exposure. The current review is aimed at updating the results of recent studies (2012-2022) focused on determining the levels of PBDEs in food samples, as well as the dietary intake of these compounds. We have revised studies conducted over the world. The current information on the concentrations of PBDEs in food and their dietary intake is now much more notable than that available in our previous review, being China the country contributing with the highest number of studies. Because of the important differences in materials and methods used in the available studies, the comparison of results is certainly complicated. However, there seems to be a general trend towards a decrease in the levels of PBDEs in foods, and consequently, in the dietary intake of these contaminants. The lack of tolerable daily intakes of PBDEs is an issue that needs to be solved for assessing human health risks of these BFRs.

Assessment of polybrominated diphenyl ethers and emerging brominated flame retardants in Pheretima (a Traditional Chinese Medicine): Occurrence, residue profiles, and potential health risks

China produces and consumes large quantities of brominated flame retardants (BFRs) as well as several other unregulated electronic waste recycling activities, causing high BFR concentrations in the natural environment. Thus, Traditional Chinese Medicines (TCMs) may be contaminated by legacy BFRs (e.g. polybrominated diphenyl ethers (PBDEs)) and emerging BFRs (eBFRs, such as decabromodiphenyl ethane (DBDPE)) during growth, processing, packaging, and transportation. Pheretima, which is a typical animal drug recorded in Chinese Pharmacopoeia, was used as an example to evaluate human exposure to BFRs through TCM intake. This study is the first to determine 25 PBDEs and 5 eBFRs in Pheretima and estimate the daily BFR intake via Pheretima-containing TCMs. Twenty-seven Shanghai Pheretima and fifty-one Guang Pheretima samples were collected between March and June 2019 in southeast China. High BFR detection frequencies were found in Pheretima, of which BDE-209 and DBDPE were the most predominant analytes. The total PBDE contents ranged from 73 pg/g to 8,725 pg/g, while that of the eBFRs varied between 115 pg/g and 2,824 pg/g. The profiles and abundances were found to be species- and origin-dependent. However, the traditional processing of Pheretima may reduce BFR residues. Based on the usual clinical doses of Pheretima and the available chronic oral reference doses of BDE-47, 99, 153, and 209, the mean (95th percentile) of the total hazard quotient was estimated to be 9.1 × 10^-5 (2.7 × 10^-4). Therefore, there is little risk related to BFR exposure for patients taking formulated Pheretima-containing TCMs. However, it is necessary to establish routine monitoring programs for the co-existence of pollutants in TCMs to perform a systematic and comprehensive risk assessment.

Absorption, distribution, metabolism, and excretion of three [14C]PBDE congeners in laying hens and transfer to eggs

Polybrominated diphenyl ethers (PBDEs) levels in environmental matrices have generally declined following their phaseout as flame retardants. The objective of this study was to determine the absorption, distribution, metabolism, and excretion of three persistent PBDEs in laying hens and their transfer into eggs. Laying hens (n = 4 per congener) received a single oral dose of BDE-99, -153, or -209 and eggs and excreta were collected daily for 7 days, then tissues were collected and analysed. Cumulative BDE-209 excretion was 93% of dose, and bioavailability was approximately 17%. Lesser amounts of BDE-99 (41%) and -153 (26%) were excreted with bioavailabilities of 87% and 79%, respectively. Phenolic metabolites were observed in excreta extracts from BDE-99 dosed birds. Cumulative transfers based on bioavailability of BDE-99, -153, and -209 to eggs were 17%, 34%, and 15%, respectively. Egg residues were primarily present in yolk (12.3%, 23.5%, and 2.1% of the total dose for BDE-99, -153, and -209, respectively). Adipose, skin, ova, intestine, and thigh muscle contained the highest levels of radioactive tissue residues. These studies demonstrate movement of PBDE residues into edible tissues and eggs of laying hens.

Polybrominated diphenyl ethers in the environment and human external and internal exposure in China: A review

Polybrominated diphenyl ethers (PBDEs) are widely used as brominated flame retardants. Because of their toxicity and persistence, some PBDEs were restricted under the Stockholm Convention in 2009. Since then, many studies have been carried out on PBDEs in China and in many other countries. In the present review, the occurrences and contamination of PBDEs in air, water, sediment, soil, biota and daily food, human blood, hair, and other human tissues in China are comprehensively reviewed and described. The human exposure pathways and associated health risks of PBDEs are summarized. The data showed no obvious differences between North and South China, but concentrations from West China were generally lower than in East China, which can be mainly attributed to the production and widespread use of PBDEs in eastern regions. High levels of PBDEs were generally observed in the PBDE production facilities (e.g., Jiangsu Province and Shandong Province, East China) and e-waste recycling sites (Taizhou City, Zhejiang Province, East China, and Guiyu City and Qingyuan City, both located in Guangdong Province, South China) and large cities, whereas low levels were detected in rural and less-developed areas, especially in remote regions such as the Tibetan Plateau. Deca-BDE is generally the major congener. Existing problems for PBDE investigations in China are revealed, and further studies are also discussed and anticipated. In particular, non-invasive matrices such as hair should be more thoroughly studied; more accurate estimations of human exposure and health risks should be performed, such as adding bioaccessibility or bioavailability to human exposure assessments; and the degradation products and metabolites of PBDEs in human bodies should receive more attention. More investigations should be carried out to evaluate the quantitative relationships between internal and external exposure so as to provide a scientific basis for ensuring human health.

Environmental pollution and human body burden from improper recycling of e-waste in China: A short-review

BRIEF BACKGROUND

E-waste generation has become a serious environmental challenge worldwide. The global quantity of e-waste was estimated 44.7 million metric tons (Mt) in 2016. The improper recycling of e-waste is still a challenging issue in developing countries.

OBJECTIVE

The objectives of this a review article to present comprehensive information of recent studied on environment pollution and effect on human health in China.

METHOD

The search engines consulted, period of publications reviewed 2015-2018. For search study, we used different key words: 'improper recycling', 'primitive recycling,' 'backyard recycling,' 'e-waste,' 'WEEE', and the studies related to improper recycling of e-waste.

RESULTS

According to reports, the e-waste recycled by unorganized sectors in China. These unorganized sector workers daily go for work, such as e-waste collection from consumer house and manual dismantling of e-waste by using simple method, at unauthorized workshop. These backyard workshop are reported in small clusters in or around city e.g., Qingyuan village; Taizhou, Longtang Town, Guiyu, nearby Nanyang River and Beigang River in China.

DISCUSSION

The earlier reported studies directed the heavy metals effect (causing effects both acute and chronic effects; respiratory irritation, reproductive problem, cardiovascular and urinary infection/disease) on human health. According the reports, the improper recycling of e-waste which need to be address for the environment protection and prevention of public health risk. However, if e-waste exposure is not avoided very well, the associated contamination will be continuing, and simultaneously needful to increase the awareness for proper e-waste management in China.

CONCLUSIONS

In order to solve the e-waste problem in China, more detail research is needed. Furthermore, for environment protection and health safety, the proper e-waste dismantling techniques, environmentally sound management, and the regular monitoring are very important.