污染問題~急~十分

air pollution
water pollution
sound pollution
land pollution
marine pollution

1)pollutants such as CFCs CO2 SO2 NOx
2)pollutants from farm , industries and domestic
3)noise
4)rubbish
5)pollutants from farm , industries and domestic

Radioactive waste is waste type containing radioactive chemical elements that does not have a practical purpose. It is sometimes the product of a nuclear process, such as nuclear fission. The majority of radioactive waste is "low-level waste", meaning it has low levels of radioactivity per mass or volume. This type of waste often consists of items such as used protective clothing, which is only slightly contaminated but still dangerous in case of radioactive contamination of a human body through ingestion, inhalation, absorption, or injection. In the US alone, the DOE acknowledges that there are "millions of gallons of radioactive waste" as well as "thousands of tons of spent nuclear fuel and material" and also "huge" quantities of contaminated soil and water. The Fernald site in Florida for example had "31 million pounds of uranium product", "2.5 billion pounds of waste", "2.75 million cubic yards of contaminated soil and debris", and a "223 acre portion of the underlying Great Miami Aquifer had uranium levels above drinking standards". The United States currently has at least 108 sites it currently designates "sacrifice zones", areas that are contaminated and unusable, sometimes many thousands of acres[American Scientist Jan/Feb 2007](&DOE)[1] The DOE wishes to try and clean or mitigate many by 2025, however it acknowledges that some will never be completely remediated, and just in one of these 108 larger designations, Oak Ridge, there were for example at least "167 known contaminant release sites" in one of the three subdivisions of the 37,000 acre site. Some of the US sites were smaller in nature, however, and cleanup issues were simpler to address. The issue of disposal methods for nuclear waste was one of the most pressing current problems the valuable international nuclear industry faced when trying to establish a long term energy production plan, yet there was hope it could be safely solved. In the US, the DOE acknowledged much progress in addressing the waste problems of this vital and critical industry, and successful remediation of some contaminated sites, yet also complications and setbacks in handling the issue properly and cost effectively. In other countries with lower ability or will to maintain environmental integrity the issue would be more problematic.

Light pollution is excess or obtrusive light created by humans. Among other effects, it can cause adverse health effects, obscures stars to city dwellers, interferes with astronomical observatories, wastes energy and disrupts ecosystems. Light pollution can be construed to have two main branches: (a) annoying light that intrudes on an otherwise natural or low light setting and (b) excessive light, generally indoors, that leads to worker discomfort and adverse health effects. Since the early 1980s, a global dark-sky movement has emerged, with concerned people campaigning to reduce the amount of light pollution.

Light pollution is a side effect of industrial civilization. Its sources include building exterior and interior lighting, advertising, commercial properties, offices, factories, streetlights, and illuminated sporting venues. It is most severe in highly industrialized, densely populated areas of the United States, Europe, and Japan, but even relatively small amounts of light can be noticed and create problems.

With recent advances in private spaceflight, the prospect of space-based orbiting billboards appearing in the near future has provoked concern that such objects may become another form of light pollution. With this in mind, the United States Federal Aviation Administration sought permission, in May 2005, to enforce a law prohibiting "obtrusive" advertising in earth orbit [1] [2]. Similar intentions are yet to be expressed by authorities in most other countries, however.

light pollution(光污染)都係近年香港有的污染之一