To help Chesapeake Bay cleanup efforts, Virginia should join Maryland and the District in banning the sale of laundry detergents containing phosphates, Sen. Joseph V. Gartlan Jr. (D-Fairfax) said yesterday.

Gartlan conducted a news conference with representatives of the Chesapeake Bay Foundation and other groups supporting the ban, which the senator has proposed in a bill before the 1986 General Assembly session. The bill is part of regional efforts to clean up the polluted bay.

Joseph Maroon, executive director of the foundation in Virginia, said household laundry detergents account for most of the phosphorus from cleaning sources. "Nearly one-quarter of the phosphorus treated at sewage treatment plants comes from laundry detergents," Maroon said.

Phosphates are water nutrients and contribute to algae growth. Proponents of the ban say phosphates cause too much algae growth, which chokes off oxygen needed by fish and water vegetation.

"Two complementary strategies are needed to deal with Virginia's nutrient enrichment problem, both long term and short term," said Gartlan.

The immediate need, Gartlan said, is to ban phosphorus detergent sales to reduce the nutrient problem now.

"Less phosphorus entering the plants means lower operation and maintenance costs," he said.

There will be a public hearing today on Gartlan's bill.