The Tennessee Department of Environment and Conservation has made a serious mistake in changing its health standard for traces of mercury in fish. (“State issues warnings for consuming fish,” April 27)

The 0.3 parts-per-million standard TDEC has adopted is called an “ambient water quality criterion.” It refers to the safety of drinking water, not the healthfulness of eating fish swimming in that water. A more appropriate standard, used by the Food and Drug Administration, is the 1.0 part-per-million “action level.” Even this higher standard, according to the FDA, is 10 times lower than the lowest levels associated with adverse effects.

Worse, TDEC is ignoring the best science on the subject. In March, the prestigious medical journal The Lancet published a major government-funded study that found no reason for government warnings about mercury in fish. Of the thousands of young mothers in this research, those who ate the most fish during their pregnancies — mercury and all — gave birth to children with the highest IQs.

Serious mercury science is finally moving past the activist sound bite. TDEC shouldn’t be giving fish the skull-and-crossbones treatment.