SEM-EDX analysis of heavy metals in anal papillae of Hydropsyche angustipennis larvae (Trichoptera, Insecta) as a support for water quality assessment

• Main Authors: M. Tszydel, D. Błońska, P. Jóźwiak, M. Jóźwiak
• Format: Article
• Language: English
• Published: Taylor & Francis Group 2021-01-01
• Series: The European Zoological Journal
• Subjects: bioindicator; contamination; morphological abnormalities; sublethal effects; caddisflies
• Online Access: http://dx.doi.org/10.1080/24750263.2021.1931490

Anal papillae of caddisflies are peripheral organs responsible for osmoregulation and detoxification. Investigation of morphological abnormalities in the anal papillae of Hydropsyche angustipennis enriched with using SEM-EDX analysis (scanning electron microscopy-energy dispersive X-ray analysis), was used to assess heavy metal pollution levels in urban streams receiving surface runoff. Heavy metal ions not previously detected in water and tissue samples by commonly used methods (e.g., AAS) were detected using SEM-EDX method. Analysis of heavy metal in the anal papillae revealed the presence of 11 elements (Fe>Mo>Mn≥Al>Cu>Pb≥Ni>Co≥As≥Ti≥V). Morphological irregularities were most frequently observed in larvae from the most contaminated streams. Most of the individuals collected from streams flowing through the city center and included in the sewage system had morphological abnormalities (~70%), contrary to the reference site (~10%). In pale, normal-shaped papillae the quantity of heavy metals was almost 10 times lower compared to darkened papillae. The present study confirms that SEM-EDX microscopy is an effective method as a support of standard heavy metal bioassays, especially if there is a necessity to detect trace elements in very small amounts of the tested material.