Historical record of polychlorinated biphenyls in a sediment core from Lake Biwa, Japan: Significance of unintentional emission and weathering signals revealed by full congener-specific analysis

Association between polychlorinated biphenyls and hypertension risk: a systematic review and meta-analysis

Background and Aim

Hypertension (HTN) is a widespread global health challenge, and its increasing prevalence is attributed to individual and environmental risk factors. Persistent organic pollutants (POPs), especially polychlorinated biphenyls (PCBs), contribute to cardiovascular risk by accumulating in fatty tissues, which leads to oxidative stress and vascular inflammation. This review and meta-analysis aimed to investigate the association between PCB exposure and hypertension.

Methods

Adhering to the PRISMA 2020 guidelines, data sources such as PubMed, Scopus, Web of Science, and Google Scholar were systematically searched up to July 2024 to find observational studies on the link between PCBs and hypertension risk. Studies were reviewed and chosen according to established inclusion and exclusion criteria, focusing on observational studies examining PCB exposure and hypertension risk. Independent reviewers conducted data extraction, and the quality of studies was evaluated using the JBI critical appraisal tool. A meta-analysis with a random-effects model was conducted to determine combined odds ratios (ORs) for hypertension linked to total PCB exposure and specific PCB types.

Results

Of the 494 records identified, 21 studies met the inclusion criteria, comprising 5 cohort studies, 15 cross-sectional studies, and one case-control study, totaling 51,514 participants. Exposure to total PCBs correlated with an elevated risk of hypertension (OR = 1.78, 95% CI: 1.30-2.44). Dioxin-like PCBs were also associated with a heightened risk (OR = 1.54, 95% CI: 1.24-1.90), while non-dioxin-like PCBs were not significantly linked (OR = 1.16, 95% CI: 0.81-1.66). Among individual congeners, PCB-74, PCB-118, PCB-105, and PCB-153 were significantly related to higher hypertension risk.

Conclusion

These findings indicate a positive correlation between PCB exposure and hypertension, particularly with dioxin-like PCBs and certain PCB congeners. Additional research is necessary to clarify the mechanisms involved and to promote measures for reducing PCB exposure, particularly in high-risk populations.

Systematic Review Registration

https://www.crd.york.ac.uk/prospero/display_record.php?ID=CRD42024595223, PROSPERO (CRD42024595223).

Centurial deposition records of polychlorinated biphenyls and organochlorine pesticides in sediment cores from a plateau deep-water lake of China: Significance of anthropogenic impacts, transformation signals and ecological risks revealed by full congener analysis

Lake Fuxian, the largest deep freshwater lake in China, has been suffering from increasing ecological and environmental issues along with the rapid urbanization and industrialization in the past 40 years. To better understand the historical pollution of persistent organic pollutants (POPs) in Lake Fuxian, comprehensive analyses of 209 polychlorinated biphenyl (PCB) congeners and 20 organochlorine pesticides (OCPs) were conducted in two intact sediment cores (Core V1 and Core V2). The total mass concentrations of PCBs ranged from 7.60 to 31.47 ng/g (dry weight basis) and 5.55 to 28.90 ng/g during the period of 1908-2019 in Core V1 and 1924-2019 in Core V2, respectively. PCBs exhibited a consecutive increasing trend from 1940s to 2019 in Core V1. The temporal trend of PCBs in Core V2 basically matched to the history of PCB usage and prohibition in China (increasing from 1940s to mid-1960s, a remarkable drop in mid-1970s, and then increasing until 2019). Moreover, low-chlorinated PCBs were dominant among PCB homologues. Mono-CBs, di-CBs, tri-CBs and tetra-CBs accounted for 86.71 %-98.57 % in sediment segments. The PCB sources included unintentional emission and atmospheric deposition, as well as biological transformation. The total mass concentrations of OCPs ranged from 0.74 to 3.82 ng/g in Core V1 and 0.35 to 2.23 ng/g in Core V2, respectively. Similar trend was observed in the two sediment cores with peaks in the early 1990s. The predominant OCPs were γ-hexachlorohexane (γ-HCHs), dieldrin and p,p'-DDD. The ecological risks posed by PCBs and p-p'-DDD in Lake Fuxian were relatively low. In contrast, dieldrin might pose a potential threat to exposed organisms and apparently adverse ecological effects were caused by γ-HCH. This study will provide important baseline information on historical POPs contamination of Lake Fuxian.

Trends of legacy and emerging organic contaminants in a sediment core from Cienfuegos Bay, Cuba, from 1990 to 2015

Legacy and emerging organic pollutants pose an ever-expanding challenge for the marine environment. This study analysed a dated sediment core from Cienfuegos Bay, Cuba, to assess the occurrence of polychlorinated biphenyls (PCBs), organochlorine pesticides (OCPs), polybrominated diphenyl ethers (PBDEs), alternative halogenated flame retardants (aHFRs), organophosphate esters (OPEs), and phthalates (PAEs) from 1990 to 2015. The results evidence the continuing presence of historical regulated contaminants (PCBs, OCPs, and PBDEs) in the southern basin of Cienfuegos Bay. PCB contamination declined since 2007, likely in response to the gradual global phasing out of PCB containing materials. There have been relatively consistent low accumulation rates for OCPs and PBDEs at this location (in 2015 approximately 1.9 and 0.26ng/cm²/year, respectively, with 2.8ng/cm²/year for Σ₆PCBs), with indications of recent local DDT use in response to public health emergencies. In contrast, sharp increases are observed between 2012 and 2015 for the contaminants of emerging concern (PAEs, OPEs, and aHFRs), and in the case of two PAEs (DEHP and DnBP) the concentrations were above the established environmental effect limits for sediment dwelling organisms. These increasing trends reflect the growing global usage of both alternative flame retardants and plasticizer additives. Local drivers for these trends include nearby industrial sources such as a plastic recycling plant, multiple urban waste outfalls, and a cement factory. The limited capacity for solid waste management may also contribute to the high concentrations of emerging contaminants, especially plastic additives. For the most recent year (2015), the accumulation rates for Σ₁₇aHFRs, Σ₁₉PAEs, and Σ₁₇OPEs into sediment at this location were estimated to be 10, 46 000, and 750ng/cm²/year, respectively. This data provides an initial survey of emerging organic contaminants within this understudied region of the world. The increasing temporal trends observed for aHFRs, OPEs, and PAEs highlights the need for further research concerning the rapid influx of these emerging contaminants.