Oils and petroleum are ever-present

Oils and petroleum are ever-present pollutants in the modern environment, whether
from the used oil of private motorists or spillage from oil tankers. At sea, oil slicks are
responsible for the deaths of many birds. Very few birds that are badly contaminated
recover, even after de-oiling and hand feeding. Oil is deposited on rocks and sand as
WATER AND SOIL POLLUTANTS 43
well, thus preventing the beaches from being used for recreation until after costly clean
up. Shore animals, such as crabs, shrimp, mussels, and barnacles, are also affected by
the toxic hydrocarbons they ingest. The subtle and perhaps potentially more harmful
long-term effects on aquatic life are not yet fully understood.
Volatile organic compounds (VOCs) are other common groundwater contaminants.
They include halogenated solvents and petroleum products, collectively referred to as
VOCs. Both groups of compounds are used in large quantities by a variety of industries,
such as degreasing, dry cleaning, paint, and the military. Historically petroleum
products were stored in underground tanks that would erode, or were spilled onto
soil surfaces. The EPA’s National Priority List includes 11 VOCs: trichloroethylene,
toluene, benzene, chloroform, tetrachloroethylene, 1,1,1-trichloroethane, ethylbenzene,
trans-1,2-dichloroethane, xylene, dichloromethane, and vinyl chloride.
The physical and chemical properties of VOCs permit them to move rapidly into
groundwater, and almost all of the previously mentioned chemicals have been detected
in groundwater near contaminant sites. High levels of exposure can cause headache,
impaired cognition, and kidney toxicities. At levels of exposure most frequently encountered,
cancer and reproductive effects are of most concern, particularly childhood
leukemia.
Low molecular weight chlorinated hydrocarbons are a by-product of the chlorination
of municipal water. Chlorine reacts with organic substances commonly found in water
to generate trihalomethanes (THMs), such as chloroform. The main organics that have
been detected are chloroform, bromodichloromethane, dibromochloromethane, bromoform,
carbon tetrachloride, and 1,2-dichloroethane. These compounds are associated
with an increased risk of cancer. Studies in New Orleans in the mid-1970s showed that
tap water in New Orleans contained more chlorinated hydrocarbons than did untreated
Mississippi River water or well water. In addition chlorinated hydrocarbons, including
carbon tetrachloride, were detected in blood plasma from volunteers who drank treated
tap water. Epidemiologic studies indicated that the cancer death rate was higher among
white males who drank tap water that among those who drank well water.

Kết quả (Việt) 1:

Dầu và dầu là chất gây ô nhiễm bao trong môi trường hiện đại, cho dùtừ dầu được sử dụng của người lái xe tư nhân hoặc các tác động từ tàu chở dầu. Biển, slicks dầuchịu trách nhiệm về cái chết của nhiều loài chim. Rất ít các loài chim xấu bị ô nhiễmphục hồi, ngay cả sau khi de-bôi dầu và tay cho ăn. Dầu được gửi trên đá và cát làCHẤT GÂY Ô NHIỄM NƯỚC VÀ ĐẤT 43tốt, do đó ngăn ngừa các bãi biển từ được sử dụng để giải trí cho đến khi sau khi tốn kém sạchlên. Bờ biển động vật, chẳng hạn như cua, tôm, trai, và hàu, cũng bị ảnh hưởng bởihydrocarbon độc hại họ ăn. Tinh tế và có lẽ có thể gây hại hơnCác ảnh hưởng lâu dài trên cuộc sống dưới nước không được hoàn toàn hiểu rõ.Các hợp chất hữu cơ dễ bay hơi (VOC) là các chất gây ô nhiễm nước ngầm phổ biến.Chúng bao gồm halogenated dung môi và các sản phẩm dầu khí, gọi chung làVOC. Cả hai nhóm của các hợp chất được sử dụng với số lượng lớn bởi một loạt các ngành công nghiệp,chẳng hạn như loại bỏ chất béo, khô làm sạch, sơn, và quân đội. Trong lịch sử dầu khísản phẩm được lưu trữ trong các bồn chứa ngầm mà sẽ xói mòn, hoặc đã được đổ vàobề mặt đất. Danh sách ưu tiên quốc gia của EPA bao gồm 11 VOC: trichloroethylene,toluene, benzen, cloroform, tetracloroethylen, 1,1,1-trichloroethane, ethylbenzene,Trans-1,2-dicloroetan, xylene, diclorometan và vinyl clorua.Các tính chất vật lý và hóa học của VOC cho phép họ di chuyển nhanh chóng vàogroundwater, and almost all of the previously mentioned chemicals have been detectedin groundwater near contaminant sites. High levels of exposure can cause headache,impaired cognition, and kidney toxicities. At levels of exposure most frequently encountered,cancer and reproductive effects are of most concern, particularly childhoodleukemia.Low molecular weight chlorinated hydrocarbons are a by-product of the chlorinationof municipal water. Chlorine reacts with organic substances commonly found in waterto generate trihalomethanes (THMs), such as chloroform. The main organics that havebeen detected are chloroform, bromodichloromethane, dibromochloromethane, bromoform,carbon tetrachloride, and 1,2-dichloroethane. These compounds are associatedwith an increased risk of cancer. Studies in New Orleans in the mid-1970s showed thattap water in New Orleans contained more chlorinated hydrocarbons than did untreatedMississippi River water or well water. In addition chlorinated hydrocarbons, includingcarbon tetrachloride, were detected in blood plasma from volunteers who drank treatedtap water. Epidemiologic studies indicated that the cancer death rate was higher amongwhite males who drank tap water that among those who drank well water.