Hispanics are exposed to more environmental health threats on average than the rest of the population, according to a report released Wednesday by an environmental group.

Because of where many Hispanics live — and the types of work many do — they are particularly threatened by waterborne diseases, air pollution, pesticides and contaminants such as lead and mercury, the Natural Resources Defense Council said.

The group called on the government to fund more studies on the effects of environmental health hazards, step up outreach programs to Hispanic communities and slap restrictions on polluters.

Along the 2,000 mile U.S.-Mexico border, 1.5 million Hispanics live in shantytowns that typically lack safe drinking water and adequate waste treatment facilities, putting them at high risk of contracting giardiasis, hepatitis and cholera, according to the report.

Since 1994, Mexico and the United States have invested approximately $3.1 billion to improve living conditions along the border, the report said. The U.S. Government Accountability Office estimated an additional $3.2 billion is needed.

Another group of Hispanics suffering from environmental health threats are farmworkers, who along with their families are routinely exposed to toxic pesticides, the report said.

"They're just being doused with chemicals," said Dianne Saenz, a spokeswoman for Physicians for Social Responsibility.

Regular exposure to pesticide residues can increase the risk of lymphoma, prostate cancer and childhood cancers, the report said.

Most Hispanics live in urban areas, where polluted air may increase the risk of cancer and asthma, according to the report.

About two-thirds of U.S. Hispanics — roughly 25.6 million people — live in areas that fall below the federal government's air quality standards, the report said. These include the U.S.-Mexico border, the Central Valley of California and the cities of Chicago, New York, Phoenix and Houston.