Answer: Mercury has been well known as an environmental pollutant for several decades. As early as the 1950's it was established that emissions of mercury to the environment could have serious effects on human health. These early studies demonstrated that fish and other wildlife from various ecosystems commonly attain mercury levels of toxicological concern when directly affected by mercury-containing emissions from human-related activities. Human health concerns arise when fish and wildlife from these ecosystems are consumed by humans.
During the past decade, a new trend has emerged with regard to mercury pollution. Investigations initiated in the late 1980's in the northern-tier states of the U.S., Canada, and Nordic countries found that fish, mainly from nutrient-poor lakes and often in very remote areas, commonly have high levels of mercury. More recent fish sampling surveys in other regions of the U.S. have shown widespread mercury contamination in streams, wet-lands, reservoirs, and lakes. To date, 33 states have issued fish consumption advisories because of mercury contamination.
These continental to global scale occurrences of mercury contamination cannot be linked to individual emissions of mercury, but instead are due to widespread air pollution. When scientists measure mercury levels in air and surface water, however, the observed levels are extraordinarily low.
Explanation:
Answer:
negative feedback
Explanation:
Insulin reduces blood sugars when the levels are high in the blood. The hormone is produced by the pancreas and binds on receptors of cells. This initiates cell signaling mechanisms that signal the cell absorb sugars. When the blood sugars get back to normal, insulin production is reduced.
On average, women live longer than men
Answer:
Ohm's law
Explanation:
Ohm's law states that the potential difference across the ends of the conductor is directly proportional to the current passing through it.
∴V∝I
Answer:
365 1/4 times
Explanation:
Earth rotates 365 1/4 times