题目内容
is usually a healthy source of protein in the diet, there may be several reasons to avoid biting into a forkful
of fish. Before you break out the tartar sauce, learn some facts about fish to keep yourself and the
environment healthy.
Some fish may contain harmful chemicals, which can be the result of both natural causes and water
pollution. Mercury is a poisonous chemical, which occurs naturally in oceans and the Earth's crust, but
also comes from manmade sources, such as pesticides, burning garbage, and the releasing of fossil fuels.
Polychlorinated biphenyls (PCBs), a group of chemicals, can also be found in some fish. These
dangerous manmade chemicals were used in many industries until 1977, when they were banned. PCBs
were released or leaked into the air and water and have been transported around the globe.
How do mercury and PCBs end up in fish and the food supply? When they are released into the air,
they attach themselves to particles. These particles settle on the ground and in the water and are
eventually eaten by microscopic organisms. Small fish eat the microorganisms, and large fish eat the small
fish and on up the food chain.
Because they can negatively affect your health, the U. S. Environmental Protection Agency advises
that kids younger than 15 years old avoid fish that contain high levels of mercury and PCBs. These
include shark, swordfish, king mackerel, and tilefish.
There are also many types of fish that are good for you, but because of overfishing are in danger of
being wiped out. Some are being fished in the wild so much that they cannot reproduce fast enough to
survive. Others are being farmed in ways that are not environmentally friendly. These fish include red
snapper, Atlantic salmon, blue fin tuna, and king crab.
Despite these problems, there are several fish that are both healthy and sustainable, such as Alaskan
salmon, American catfish, Pacific cod, and several farmraised fish and shellfish.
【文章大意】 鱼虽富含蛋白质, 但本文却建议小孩子不要吃鱼以及说明了其中的原因.
B. Mercury and PCBs-particles-organisms-fish-food supply
C. Mercury and PCBs-particles-fish-organisms-food supply
D. Mercury and PCBs-organisms-ground and water-fish-food supply
B. particles
C. microscopic organisms
D. mercury and PCBs
B. King crab;king mackerel;Pacific cod.
C. Pacific cod;Alaskan salmon;American catfish.
D. Pacific cod;Atlantic salmon;swordfish.
B. overfishing is the main cause of fish poisoning
C. most types of fish can be safely raised on fish farms
D. the government should ban children under 15 from eating fish
B. if you want to be more environmentally friendly, eat less fish
C. PCBs were not allowed to be used in food industry before 1977
D. adults might be less affected by high chemical levels in fish
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