LOS ANGELES — Residents of modest neighborhoods near three of the largest oil refineries in California called on the Environmental Protection Agency on Wednesday to crack down on plant emissions, saying the pollution is choking their children and endangering their health.Residents of the oil-rich Wilmington area of Los Angeles were among 15 speakers to address the morning session of an EPA hearing about a proposed rule requiring stricter emission controls and monitoring standards.Several speakers said they have suffered from asthma and other ailments they believe were caused by the refineries near the ports of Los Angeles and Long Beach."My own family suffers from asthma," said Evelyn Knight, who has lived in neighboring Long Beach since 1968. "I had a brother die from lung cancer who never smoked. Many friends have come down with cancer."Community organizer Shabaka Heru said children whose lungs and other organs are still developing are particularly at risk."We have children who have inflated incidents of asthma," he said.The EPA proposal would require the petroleum industry adopt new technology to better monitor emissions of the carcinogen benzene, upgrade storage tank emission controls and ensure waste gases are properly destroyed.Refineries would also have to improve perimeter monitoring to get a clearer picture of how much toxic pollution is drifting into communities. Those findings would have to be made available to the public.EPA officials estimate such actions could reduce toxic air emissions from refineries by as much as 5,600 tons a year.Three executives with the petroleum industry told the three-member hearing panel that the proposed changes could cost the industry as much as a billion dollars and provide little in the way of improved air quality."Air quality in the United States has improved significantly, continues to improve, and our industry is doing its part to contribute to the success," said Howard Feldman, director of regulatory and scientific affairs for the American Petroleum Institute."It goes without saying that the safe operation of our refineries to protect our workers and the community is our No. 1 priority," he added.Members of the community disagreed."There will never be a solution until the perpetrators of the pollution in our community take full responsibility and have zero pollution," Knight said.Flavio Mercado of Wilmington brought a jar of black gunk he said was particulate matter from a refinery that had been collected from a neighborhood. Photos of refineries belching plumes of huge, black smoke as neighborhood children play in the foreground were displayed.United Steelworkers member David Campbell said his union also supports the tougher standards."Our union sees this as a benefit to not only our members who work inside the facilities but also to our friends and families who work and live outside the fence line," he said.The hearing, attended by about 40 people, adjourned shortly before noon and was to resume Wednesday evening, when 15 more people were scheduled to speak.Another hearing is scheduled for Aug. 5 in Texas, and the EPA has set aside a 60-day period for people to submit written comments. No action is expected before next year.The Wilmington area has more than 6,000 oil wells and is home to three of California's major oil refineries. The 9-square-mile area with 53,000 residents also includes the third-largest oil field in the contiguous United States.The proposed rules changes came from the resolution of a lawsuit brought in 2012 by the environmental groups Earthjustice and Environmental Integrity Project on behalf of people directly affected by emissions from refineries in Louisiana, Texas and California.The action accused the EPA of shirking its responsibility under the Clean Air Act by neglecting to review and possibly revise refinery emission standards every three years. The EPA has not implemented new emission standards since 1995.