Roast those dioxins away.

Roast those dioxins away

Dioxins, PCBs and other chlorinated hydrocarbons tend to settle into the sediment of the waterways they enter. That's why bottom-feeding fish, such as carp, can accumulate relatively high levels. In some Michigan rivers and streams, bottom feeders have accumulated up to 120 parts per trillion of TCDD, the most toxic of the dioxins. But a new Michigan State University study indicates that cooking can reduce that contamination dramatically.

Nancy C. Stachiw, Mary Zabik and their co-workers charbroiled and roasted restructured carp filets (chopped carp bits pressed into steaks) made from fish netted in Lake Huron's Saginaw Bay. Although the TCDD level of all filets was lower after cooking, certain methods proved more effective in eliminating the pollutant. For example, among filets cooked to an internal temperature of 60[deg.] C (medium rare), initial levels of TCDD contamination--about 40 parts per trillion--dropped 46 percent in those charbroiled, 37 percent in those roasted under covers, but just 24 percent in those roasted uncovered. Fish cooked to an internal temperature of 80[deg.] C (well done) lost even more TCDD -- between 50 and 60 percent, depending on the cooking method.

These differences among cooking temperatures and techniques are impressive enough to justify advising consumers to cook fish they suspect of being contaminated at high head and/or to a well-done stage, the East Lansing scientists write in the July/August JOURNAL OF AGRICULTURAL AND FOOD CHEMISTRY. Moreover, their work shows, a 12 percent increase in surface area (per unit weight) reduced cooked-filet TCDD contamination by 12 percent.

Where does the TCDD go? Although the scientists haven't measured its levels in the drippings, Zabik says it's reasonable to expect that's where the fat-stored chemical ends up--so don't feed carp drippings to your cat.