Microplastics, human health and the environment

Transcription

1 Micropastics, human heath and the environment Second meeting of the Ad Hoc Open-Ended Expert Group on Marine Litter and Micropastics 3 December 2018 Bruce Gordon and Jennifer De France

2 Micropastics, human heath and the environment Background Emerging contaminant generating pubic concern Intense media coverage Potentia heath impact?

3 Micropastics: Context to WHO response WHO reguary issues heath-based guideines on heath and environment GPW13: the areas of environment and cimate change have been prioritized. WHO cooperates with key partners, such as UN Environment, through recent strategic agreements. Emerging issues, such as pastics are identified as important issues in the heath and environment department

4 Micropastics: Context to WHO response WHO Guideines for Drinking-water Quaity Supports countries in deveoping drinking-water quaity reguations and standards 500+ pages covering, chemica, microbia, radioogica and protection and contro aspects Incudes an assessment of ~150 chemicas Guideine vaues are estabished for chemicas when there is credibe evidence of occurrence in drinking-water and evidence of actua or potentia toxicity

5 Micropastics: WHO Technica Work Expert meeting on Micropastics in Drinking-water (Juy 2018 in Singapore) WHO Review of Micropastics and Drinking-water (for March 2019) Systematic review of data quaity (Micropastics in Freshwaters and Drinking Water forthcoming journa artice) Broader human heath risk assessment covering additiona environmenta exposure routes (air, food, etc.), to be fuy initiated in 2019

6 Outine for WHO Report on Micropastics in Drinking-water Introduction Uses of pastics Occurrence of micropastics in water Heath effects and risk assessment for micropastics in drinking water Remova in drinking water and wastewater treatment Preventing micropastic contamination in water sources Concusions, recommendations (incuding reated to research) and knowedge gaps References

7 WHO Report on Micropastics in Drinking-water Target audience Drinking-water reguators, poicy makers and water suppiers Scope Focus on human heath (imited information on ecotoxicity) Reative contribution from drinking-water compared to other exposure routes

8 Concentration of micropastics in water Systematic review Quantitative quaity assessment of samping, extraction and detection methods of water studies Assessed botted, tap, surface, ground and wastewater studies Assessed against nine quaity criteria Summary of information on poymers identified, shape and size

9 Concentration of micropastics in water Systematic review Quantitative quaity assessment of samping, extraction and detection methods of water studies Assessed botted, tap, surface, ground and wastewater studies Assessed against nine quaity criteria Summary of information on poymers identified, shape and size Outook Improvements are needed in samping, extraction and anaysis, incuding consideration of standard methods Data gaps: Concentrations in drinking-water Information on size, shape, composition, source

10 Heath effects assessment No information on the impact to human heath

11 Heath effects assessment No information on the impact to human heath Mutipe eements of risk to consider Monomers, additives and adsorbed toxins Sma partices Biofims

12 Heath effects assessment Pathogens in biofims Pastics provide an idea substratum for biofim formation in the environment Limited evidence suggests micropastics provide an idea condition for the coection, transport and dispersion of microorganisms Occurrence of micropastic associated biofims and reated heath risks unknown

13 Heath effects assessment Sma pastic partices Limited data on toxicity No human studies Most testing has been imited to aquatic organisms Limited data on bioavaiabiity Micropastics: absorption unikey for partices > 150 μm Micropastics: imited absorption ( 0.3%) for smaer micropastics? Nanopastics: up to 7% uptake (PS) with widespread distribution in the body Limited data on partice characteristics that are most predictive of toxicity

14 Heath effects assessment Monomers, additives and adsorbed toxins Additives of toxicoogica concern: Phthaates (pasticizer) PBDE (fame retardant) BPA (antioxidant) Lead (coorant, stabiizer) Adsorbed toxins Hydrophobic nature of pastic partices encourages adsorption of hydrophobic chemicas, e.g. POPs incuding PAHs

15 Heath effects assessment Monomers, additives and adsorbed toxins (cont.) Limited data on Reease of monomers and additives from pastic upon aging and weathering Reease of monomers and additives in the GI tract Desorption of adsorbed toxins in the GI tract Exposure assessment to be conducted Conservative assumptions given significant data gaps

16 Next Steps Finaize draft report with Expert Group Targeted peer review Pubication + preparation of fact sheet/executive summary Literature review and scoping meeting for broader assessment on micropastics in the environment and human heath Possibe update of drinking-water assessment