Advertisement

Gee, thanks Mom: California fish pass contaminants to offspring

Share

This article was originally on a blog post platform and may be missing photos, graphics or links. See About archive blog posts.

Fish swimming in the Sacramento River, a major source of drinking-water supplies, aren’t just picking up industrial and farm chemicals from the water and what they eat, they are passing the toxins on to their babies.

Testing by UC researchers found that striped bass eggs collected from the river were contaminated with a harmful mixture of pesticides, flame retardants and industrial chemicals that interfere with fish development and growth.

Advertisement

The contaminants included 16 pesticides -- some currently in use and some long-banned, like DDT -- as well as the flame retardant PBDE (polybrominated diphenyl ethers) and PCBs (polychlorinated biphenyls), formerly used in the manufacture of electrical transformers.

Larvae from the river eggs developed abnormally, grew more slowly and were significantly smaller than baby fish from a hatchery. At 5 days old, the river larvae exhibited smaller brains, shrunken livers and depleted energy stores in their yolks, leaving them handicapped as they began their lives.

The contamination is likely contributing to the troubles of striped bass, one of several sharply declining fish species in the Sacramento-San Joaquin River Delta.

The findings, published this week in the Proceedings of the National Academy of Sciences, also raise questions about human impact.

‘If the fish living in this water are not healthy and are passing on contaminants to their young, what is happening to the people who use the water, are exposed to the same chemicals or eat the fish?’ wondered David Ostrach, lead author of the study and a research scientist at the UC Davis Center for Watershed Sciences.

‘We should be asking hard questions about the nature and source of these contaminants, as well as acting to stop the ongoing pollution and mitigate these current problems.’

Advertisement

One of California’s major rivers, the Sacramento flows into the delta, which is part of the largest estuary on the West Coast and a source of drinking and irrigation water for much of the state.

--Bettina Boxall

Advertisement