A vote on the bill had been expected in the full U.S. Senate this week as part of a deal between Democratic and Republican leaders of the Senate Veterans Affairs Committee, McClatchy Newspapers reported.
But Sen. Jim DeMint, R-S.C., has put a procedural hold on the bill, expressing concern about fraud by those whose illnesses were not due to water contamination.
Wesley Denton, a spokesman for DeMint, said in a statement DeMint "does not oppose the underlying bill and has been working in good faith to stop fraudulent claims that would divert resources away from affected veterans and their families."
As many as 1 million people at Camp Lejeune may have been exposed to drinking water poisoned with trichloroethylene, tetrachloroethylene, benzene and vinyl chloride. The contamination has been linked by some medical experts to birth defects, childhood leukemia and other cancers.
A bill agreed on last month by the House and Senate veterans affairs committees would provide healthcare for people who lived or worked at Camp Lejeune from Jan. 1, 1957, through Dec. 31, 1987. Military personnel and family members would be provided healthcare if they lived or worked at least 30 days on the Marine Corps base.
As many as 750,000 Marine veterans and family members could receive healthcare.
The bill also includes other provisions, including expanding healthcare benefits for disabled veterans, reauthorizing programs to help homeless veterans and improving claims processing.
Sen. Richard Burr, R-N.C., the Senate bill's lead sponsor, said in a statement he's "disappointed that passage of this very important bill has been slowed. I am confident, however, that we can pass this bill quickly and finally begin to help those who were exposed to water contaminated with known human carcinogens."
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