None of the seven toxic waste dump sites in Maryland and Virginia targeted yesterday by the Environmental Protection Agency for clean up constitute serious hazards to nearby residents, according to health officials in both states.

"Our view is that they are not now posing any threat to public health," said William Eichbaum, Maryland's assistant secretary for environmental programs. "Our concern is that if the dumps are left totally uncontrolled they could."

Four of what the EPA said were the nation's worst hazardous waste dumps are located in southern Virginia. Three are in Maryland and none are in the District. State and environmental officials say that most of the sites selected for EPA's $1.6 billion Superfund program have been the subject of protracted litigation.

All three of Maryland's sites, located in Cumberland, Elkton and Annapolis, have been the subject of recent legal action, according to Maryland officials who say clean-up efforts are progressing. The operator of the Cumberland County site recently served a one-year jail term for improperly disposing of chromium-bearing waste, state officials said.

Recently an Anne Arundel County judge set an April 1983 deadline and ordered that the operator of an illegal Annapolis dump located in a residential area remove drums of paint and solvent, the officials said.

One of Virginia's longest running disputes involves the Saltville Waste Disposal Ponds in southwestern Smyth County, near the North Carolina-Tennessee border. Until 1972 when the Olin Chemical Co. shut its Saltville plant, the EPA said the firm had dumped 11 million tons of mercury-contaminated chlorine and caustic soda into disposal ponds.

The material leaked out and contaminated a 50-mile stretch of the North Fork of the Holston River, which has been closed to recreational fishing since 1970. Clean-up efforts are progressing, according to William Gilley, Virginia's hazardous waste administrator.

Other hazardous dumps in Virginia include the former Roanoke site of Matthews Electroplating where state officials said cyanide and chromium were dumped into a sinkhole and may have infiltrated a water supply for several dozen homes nearby. A similar situation, the officials said, exists near Chisman Creek in York County, where effluent containing vanadium from a Virginia Electric and Power Co. plant was improperly dumped by a private contractor and contaminated shallow residential wells.

Virginia's fourth site is located on 80 acres owned by New Jersey-based U.S. Titanium site adjacent to the Piney River in Nelson County. EPA officials said that the owners improperly disposed of 80,000 tons of acid waste used in making paint and in the process killed 157,000 fish.