Biosolids

By Mario Ritter

Broadcast: October 28, 2003

This is Steve Ember with the VOA Special English Agriculture Report.
Farmers have long put animal waste on their fields. They may also use human waste. Modern ways to process waste and make it safer to use have only been developed since the nineteen-seventies.
Treated waste products are called biosolids, or 1)sludge. They contain 2)nitrogen, 3)phosphorus and 4)potassium. Biosolids are removed from the wastewater systems of cities and other communities. They are treated in several ways to kill organisms that could spread disease.
In the United States, the government says sixty-percent of all treated solid waste is used to fertilize¹ land. This includes some farmland. But the government says only one-tenth of one-percent of American farmland uses this kind of fertilizer from year to year.
There are two kinds of biosolids. Class A is considered free of any organism that could be a danger to health. These organisms include 5)viruses, 6)bacteria and 7)worms. Class B biosolids are not completely free of such organisms. So their use is restricted.
Another concern about biosolids is that they may contain chemical pollution. Many kinds of chemicals can enter wastewater systems. In the United States, the Environmental Protection Agency has rules about the presence of nine chemicals in biosolids. The E-P-A requires testing for levels of substances like 8)arsenic², 9)chromium, 10)mercury and lead.
After five years of study, the E-P-A recently decided³ not to require producers and users of biosolids to add 11)dioxins to this list. Dioxins are a group of organic chemicals that can stay for a long time in the environment. There are concerns about greater risk of cancer and other disorders⁴.
Dioxins are released by burning plastics and fuels like coal, oil and wood. They are also released by some kinds of chemical manufacturing. Paper production with the use of chlorine produces dioxins. So does cigarette smoke.
Environmental groups and others condemned⁵ the decision not to set rules for dioxins in biosolids. They point out that the use of sludge products is a leading cause of dioxin in the environment in the United States.
The E-P-A agrees that dioxins are highly 12)poisonous. But the agency has also found that levels in the environment have been greatly reduced in the last thirty years. It says there is not enough risk of new cancer cases in farmers and other people to support new rules.
This VOA Special English Agriculture Report was written by Mario Ritter.

注释：
1) sludge [ slQdV ] n.软泥, 淤泥
2) nitrogen [ 5naitrEdVEn ] n.(化)氮
3) phosphorus [ 5fCsfErEs ] n.磷
4) potassium [ pE5tAsjEm ] n.(化)钾(19号元素, 符号K)
5) virus [ 5vaiErEs ] n.(微)病毒, 毒害
6) bacteria [ bAk5tiEriE ] n.细菌
7) worm [ wE:m ] n.虫, 蠕虫
8) arsenic [ 5B:sEnik ] n.(化)砷, 砒霜
9) chromium [ 5krEumjEm ] n.铬
10) mercury [ 5mE:kjuri ] n.水银, 汞
11) dioxin [dai`Cksin] n.(化)二氧(杂)芑
12) poisonous [ 5pCiznEs ] adj.有毒的

1 fertilize   

v.使受精，施肥于，使肥沃

参考例句：

• Fertilizer is a substance put on land to fertilize it.肥料是施在地里使之肥沃的物质。
• Reading will fertilize his vocabulary.阅读会丰富他的词汇。

2 arsenic   

n.砒霜，砷；adj.砷的

参考例句：

• His wife poisoned him with arsenic.他的妻子用砒霜把他毒死了。
• Arsenic is a poison.砒霜是毒药。

3 decided   

adj.决定了的，坚决的；明显的，明确的

参考例句：

• This gave them a decided advantage over their opponents.这使他们比对手具有明显的优势。
• There is a decided difference between British and Chinese way of greeting.英国人和中国人打招呼的方式有很明显的区别。

4 disorders   

n.混乱( disorder的名词复数 )；凌乱；骚乱；（身心、机能）失调

参考例句：

• Reports of anorexia and other eating disorders are on the increase. 据报告，厌食症和其他饮食方面的功能紊乱发生率正在不断增长。 来自《简明英汉词典》
• The announcement led to violent civil disorders. 这项宣布引起剧烈的骚乱。 来自《简明英汉词典》

5 condemned   

adj. 被责难的, 被宣告有罪的 动词condemn的过去式和过去分词

参考例句：

• He condemned the hypocrisy of those politicians who do one thing and say another. 他谴责了那些说一套做一套的政客的虚伪。
• The policy has been condemned as a regressive step. 这项政策被认为是一种倒退而受到谴责。