We can't find the internet
Attempting to reconnect
Something went wrong!
Hang in there while we get back on track
Synergistic human health risks of microplastics and co-contaminants: A quantitative risk assessment in water
Summary
This study calculated the combined health risks of ingesting microplastics along with the toxic chemicals they carry, including heavy metals and plastic additives, and found that the combined hazard is far greater than from microplastics alone. Children face especially high risk, and the interaction between microplastics and co-contaminants creates synergistic effects that standard risk assessments may significantly underestimate.
The pervasive presence of microplastics (MPs) in aquatic environments, coupled with their potential to act as vectors for toxic contaminants, raises significant concerns for human health. This study quantifies the health risks associated with the ingestion of microplastics and their co-contaminants in aquatic medium, considering both individual and interactive effects. The analysis encompasses four MP types (PP, PS, PET, PE) and prevalent contaminants including heavy metals (Cr, Cu, Ni, Pb), polycyclic aromatic hydrocarbons (PAHs, expressed as BaP equivalents), and plastic additives (DEHP, DBP, BPA)-to calculate individual Hazard Quotient (HQ), interaction-based Hazard Index (HI), individual Incremental Lifetime Cancer Risk (ILCR), and interaction-based ILCR (ILCR). The mean concentration of MPs in aqueous media was determined to be 2.19 mg/L (95 % CI), and Chronic Daily Intake (CDI) values were derived from particle counts converted to mass using polymer-specific densities. Reference Dose (RfD) values were calculated using the Weight of Evidence (WoE) approach, which integrates findings from rodent toxicity studies, identifying PP and PS as having low RfD values 25 × 10⁻⁴ mg/kg bw/day and 8 × 10⁻⁴ mg/kg bw/day, respectively. HQ-based toxicity rankings indicated the order of risk as PP > PS > PE > PET. Findings revealed a pronounced HI of 18.646 × 10³ and 16.649 × 10⁶ at the 50th and 90th percentiles in children, underscoring significant synergistic effects from combined exposure to MPs and leached plastic additives. Co-contaminant scenarios further escalated health risks, with HI values reaching 52.236 in the presence of heavy metals and 53.141 with PAHs. The maximum allowable MP concentration, considering additive leaching, was estimated at 0.011 mg/L. This research highlights the need for firstly understanding the transformations of microplastic in the aquatic medium along with co-contaminants and framing regulatory measures and improved monitoring to protect human health from the growing threat of microplastic pollution. By integrating exposure modeling, dose-response assessment, and Monte Carlo simulations, the study delivers a robust framework for environmental health guidelines. It emphasizes the complex, multifaceted risks MPs pose and their associated contaminants, calling for innovative solutions to safeguard public health against this pervasive environmental challenge.
Sign in to start a discussion.
More Papers Like This
Integrative Evaluation of the Ecological Hazards by Microplastics and Heavy Metals in Wetland Ecosystem
Researchers conducted an integrative ecological hazard assessment of microplastics combined with heavy metals, evaluating their combined toxicity to aquatic organisms. The study found that co-contamination with heavy metals and microplastics poses greater ecological risk than either pollutant alone.
Fate of microplastics and emerging contaminants: Mechanisms of interactions, bioaccumulation and combined toxicity to aquatic organisms
This review summarizes how microplastics interact with other emerging contaminants in water, finding that microplastics can absorb pollutants at concentrations up to a million times higher than surrounding water and carry them into living organisms. The combined toxicity of microplastics plus these hitchhiking chemicals is often greater than either alone, and these pollutants can reach humans through the food chain.
Microplastics aggravate the bioaccumulation and toxicity of coexisting contaminants in aquatic organisms: A synergistic health hazard
Researchers conducted a quantitative meta-analysis of 870 endpoints from 40 studies to evaluate whether microplastics increase the bioaccumulation and toxicity of co-occurring contaminants in aquatic organisms. They found that microplastics significantly increased co-contaminant bioaccumulation by 31% and exacerbated toxicity by 18%, with effects manifesting as increased oxidative stress, endocrine disruption, and immunotoxicity. The study confirms that microplastics act as vectors that amplify the hazards of other environmental pollutants.
The Unseen Threat of the Synergistic Effects of Microplastics and Heavy Metals in Aquatic Environments: A Critical Review
This review examines how microplastics and heavy metals interact in water environments, finding that microplastics can attract and concentrate toxic metals on their surfaces through various chemical forces. This combination effect is a concern for human health because contaminated microplastics carrying heavy metals can be consumed through seafood, delivering a double dose of pollutants.
A review on the combined toxicological effects of microplastics and their attached pollutants
Researchers reviewed how microplastics act as carriers for other environmental pollutants — including heavy metals and persistent organic chemicals — and how these combinations produce toxic effects in organisms that are more severe than either contaminant alone. The findings highlight a complex, layered toxicity problem that affects microbes, invertebrates, and vertebrates across marine and terrestrial environments.