We can't find the internet
Attempting to reconnect
Something went wrong!
Hang in there while we get back on track
Probabilistic environmental risk assessment of microplastics in marine habitats
Summary
A probabilistic environmental risk assessment for marine microplastics — using measured concentration data and species sensitivity distributions — found low risk ratios overall but identified hotspot water bodies (harbors, coastal inlets) where MP concentrations approached or exceeded effect thresholds.
Microplastics are ubiquitous in the environment and given the large number of published hazard and exposure studies, quantitative environmental risks assessments of microplastics become feasible. We present here the first environmental risk assessment for marine waters based only on measured concentrations. The Thevariability and uncertainty of the measured data was accounted for in the exposure assessment, while probabilistic species sensitivity distributions were used for hazard assessment, from which a probability distribution was extracted for the predicted no-effect concentration (PNEC). By dividing the exposure distribution by the PNEC-distribution, we were able to calculate probabilistic risk characterisation ratios for each water body in which measurements were performed. Results show a good coverage of the world's major water bodies by measured exposure concentrations (MECs), while the hazard assessment could be improved by aligning the type of particles tested in hazard studies (size, form, polymer) to those actually found in the oceans. Overall, the mean predicted no-effect concentration (PNEC) is 3.84·106 part m-3, with Oryzias melastigma being the most sensitive species (calculated mean NOEC of 3.90·106 part m-3). Interestingly, the only type of dose descriptor that could be extracted from the literature for particles above 10-20 μm was the highest observed no effect concentration (HONEC), which indicates a very low or null toxicity of these larger MPs towards marine organisms. The mean MEC is 1.5·103 part m-3, the highest concentrations being measured in the Atlantic and Pacific Ocean. Although there is a very small overlap of the probability distribution associated with the RCR (0.00002 % of the data points), the mean RCR is 4·10-4 and therefore risks are unlikely given the available data. However, as increasing amounts of plastic reach the environment, RCRs can be expected to increase in the future.
Sign in to start a discussion.
More Papers Like This
Integrating species sensitivity distributions and toxicity thresholds: A probabilistic risk assessment of microplastics in Yazhou Bay, South China Sea
Researchers assessed microplastic abundance and ecological risk in Yazhou Bay, South China Sea, finding surface water concentrations of 3,437 n/m³ with a modeled estimate reaching 241,000 n/m³ when accounting for smaller particle sizes. Species sensitivity distribution analysis identified significant ecological risk to marine organisms at detected concentrations.
Assessment of potential ecological risk for microplastic particles
Researchers applied an ecological risk assessment framework to evaluate the hazard posed by microplastic particles across multiple environmental compartments, using species sensitivity distributions and environmental concentration data. The assessment highlighted specific particle types and size ranges that present the greatest ecological risk.
Toward an ecotoxicological risk assessment of microplastics: Comparison of available hazard and exposure data in freshwaters
Researchers compiled available exposure and toxicity data to perform the first probabilistic risk assessment of microplastics specifically in freshwater environments. The study found that while current concentrations in most freshwaters may not yet pose widespread ecological risk, localized hotspots could exceed harmful thresholds, highlighting the need for more standardized freshwater monitoring.
A probabilistic risk framework for microplastics integrating uncertainty across toxicological and environmental variability: Development and application to marine and freshwater ecosystems
Researchers developed a new probabilistic risk assessment framework for microplastics that accounts for uncertainty in how laboratory toxicity data translates to real environmental conditions. Using Monte Carlo simulation and an enhanced species sensitivity distribution model, they found that uncertainty from particle-trait alignments can drive threshold variability by up to two orders of magnitude. The framework highlights that current risk assessments may underestimate hazards and identifies key research needs for improving microplastic environmental safety thresholds.
Illustrating a Species Sensitivity Distribution for Nano- and Microplastic Particles Using Bayesian Hierarchical Modeling
Researchers developed a Bayesian hierarchical model to construct species sensitivity distributions for nano- and microplastic particles, deriving hazardous concentration thresholds to support environmental risk assessment of plastic pollution.