Exposure to a microplastic mixture is altering the life traits and is causing deformities in the non-biting midge Chironomus riparius Meigen (1804)

• Published in: Environmental pollution (1987) Vol. 262; p. 114248
• Main Authors: Stanković, Jelena, Milošević, Djuradj, Savić-Zdraković, Dimitrija, Yalçın, Gülce, Yildiz, Dilvin, Beklioğlu, Meryem, Jovanović, Boris
• Format: Journal Article
• Language: English
• Published: England Elsevier Ltd 01-07-2020
• Subjects: Chironomids; Development; Ecotoxicology; Geometric morphometrics; Microplastics; Toxicity; Development; Geometric morphometrics; Microplastics; Ecotoxicology; Toxicity; Chironomids
• ISSN: 0269-7491; 1873-6424
• DOI: 10.1016/j.envpol.2020.114248

The effect of microplastics (MP) exposure on the chironomid species Chironomus riparius Meigen, 1804 was investigated using the OECD sediment and water toxicity test. Chironomid larvae were exposed to an environmentally relevant low microplastics concentration (LC), a high microplastics concentration (HC) and a control (C). The LC was 0.007 g m−2 on the water surface + 2 g m−3 in the water column + 8 g m−2 in the sediment, and the HC was 10 X higher than this for each exposure. The size of the majority of the manufactured microplastic pellets varied between 20 and 100 μm. The MP mixture consisted of: polyethylene-terephtalate (PET), polystyrene (PS), polyvinyl-chloride (PVC) and polyamide (PA) in a ratio of 45%: 15%: 20%: 20%, respectively, for the sediment exposure; 100% polyethylene for the water column exposure; and 50% polyethylene: 50% polypropylene for the water surface exposure. Different endpoints were monitored, including morphological changes in the mandibles and mentums of 4th instar larvae, morphological changes in the wings, mortality, emergence ratio, and developmental time. A geometric morphometric analysis showed a tendency toward widening of the wings, elongation of the mentums and changing the shape of the mandibles in specimens exposed to both concentrations of microplastics. The development time of C. riparius was significantly prolonged by the MP treatment: 13.8 ± 0.5; 14.4 ± 0.6; and 15.3 ± 0.4 days (mean ± SD) in the C, LC, and HC, respectively. This study indicates that even environmentally relevant concentrations of MP mixture have a negative influence on C. riparius, especially at the larval stage.
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•Exposure to a mixture of microplastics postponed developmental time of C. riparius.•The average body mass and average body length increased.•The right female wings showed differences in the wing shape in treatments.•The mouthparts deformities of the 4th instar larvae were observed in treatments.•Low concentration of MP mixture had negative influence on C. riparius.
Developmental time of C. riparius was prolonged in treatments. Mandibles showed a tendency to widen; the medium tooth and inner lateral teeth of mentums to shorten.