Life-cycle changes and zinc shortage in cadmium-tolerant midges, Chironomus riparius (Diptera), reared in the absence of cadmium

Journal Article · Sun Jan 01 04:00:00 EST 1995 · Environmental Toxicology and Chemistry; (United States)

DOI:https://doi.org/10.1002/etc.5620140113· OSTI ID:6519789

Postma, J F; Mol, S; Larsen, H; Admiraal, W ^[1]

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1. Univ. of Amsterdam (Netherlands). Section of Aquatic Ecotoxicology

Adaptation to selected metals is known to modify life-cycle characteristics of some invertebrates and can modify the response to other metals. The reverse process, i.e., adaptation to nonpolluted conditions in a metal-tolerant strain, was studied here for a cadmium-tolerant population of the midge Chironomus riparius to detect whether this backward adaptation followed the same lines. It appeared that cadmium-tolerant populations, reared in the absence of cadmium, continued to suffer from high mortality rates and lowered larval growth rates and reproductive success. Also, some cadmium-tolerant populations accumulated more zinc than did nontolerant populations. Successive experiments in which both cadmium-tolerant and nontolerant populations were exposed to zinc indicated that the reduced growth rate and reproduction were a direct consequence of zinc shortage in tolerant midges reared in the absence of cadmium. Mortality among cadmium-tolerant midges was, however, not lowered by zinc exposure and, judged by their high mortality rates, these midges were even more sensitive to zinc than were nontolerant chironomids. It was concluded that cadmium-tolerant chironomid populations recovering from prolonged exposure are affected by an increased need for zinc as well as by an increased mortality rate as a direct consequence of their earlier adaptation process.

• OSTI ID: 6519789
• Journal Information: Environmental Toxicology and Chemistry; (United States), Journal Name: Environmental Toxicology and Chemistry; (United States) Vol. 14:1; ISSN ETOCDK; ISSN 0730-7268
• Country of Publication: United States
• Language: English

Related Subjects

560300* -- Chemicals Metabolism & Toxicology
63 RADIATION, THERMAL, AND OTHER ENVIRON. POLLUTANT EFFECTS ON LIVING ORGS. AND BIOL. MAT.
ANIMALS
ARTHROPODS
BIOLOGICAL ADAPTATION
BIOLOGICAL EFFECTS
DIPTERA
ELEMENTS
INSECTS
INVERTEBRATES
METALS
TOLERANCE
ZINC