Residents in Philadelphia panicked and purchased water after learning of a chemical spill, but officials say tap water is safe for the time being.

Philadelphia residents can continue using tap water as normal until at least 3:30 p.m. Tuesday following a chemical spill a few miles upstream of a key intake in the Delaware River. Michael Carroll, the city's deputy managing director for transportation, infrastructure and sustainability, said at a news conference Monday afternoon that water quality was being tested around the clock and that the contaminants from Sunday's spill should be clear from the river by Thursday. However, the assurances are causing confusion, concern and anger in the busy East Coast hub, where some grocery shelves are already empty of water. The spill "appears to be the result of equipment failure" at a Trinseo PLC plant that makes acrylic resins, the owner said Sunday, and it raised immediate concerns about possible health threats. Carroll also said Sunday's guidance had changed for "convoluted" reasons. South Philadelphia resident Joe Sole spoke to CNN from a grocery store parking lot as he loaded packages of bottled water into his car, saying, "I don't trust the city." At least one of the discharged chemicals, butyl acrylate, is among contaminants of concern identified in last month's train derailment in East Palestine, Ohio. Philadelphia Mayor Jim Kenney acknowledged residents' anxieties, saying the city's advice on the tap water's safety was updated "based on the time it will take river water that entered the Baxter intakes early Sunday morning to move through treatment and water mains before reaching customers." Officials reiterated advice that residents should have three days' worth of water on hand, but said it was possible that contaminants from the spill might not enter the city's water supply at all. Philadelphia Water Commissioner Randy Hayman emphasized that testing takes time. The Philadelphia Water Department provides water to more than 2 million people in Philadelphia, Montgomery, Delaware, and Bucks counties, and is posting online updates regarding the spill. Philadelphia officials initially sent out mobile phone alerts recommending residents use bottled water due to a latex product spill, but later said tap water from the Baxter Drinking Water Treatment Plant would remain safe to drink until at least the end of Monday. None of the three chemicals that leaked into the river when a latex product spilled Friday in Bristol, Pennsylvania, had been detected in Philadelphia's water system by Sunday evening. By then, however, residents had already swarmed grocery stores to stock up on bottled water as news of the spill spread. Kim Kelly, a "gallon-a-day kind of gal" who found some shelves bare at one South Philadelphia store, said she felt like someone should reimburse all of us for all the money we're spending on all this water. John Sole didn't rush out to buy bottle water after receiving the first alert Sunday, but by late Monday morning, he made the trek, conceding he and his wife were "afraid to drink the regular water." Sole didn't know how he could be convinced the tap water's safe, but he said it could just take time. The Coast Guard said 60,000 gallons of contaminated water had been collected from the spill, and no evidence of contamination plumes was seen during a flyover by the Philadelphia Police Department and Pennsylvania Department of Environmental Protection. Clean-up is focused on removing product from the storm drain system and outflow located on Mill Creek. Coast Guard pollution responders conducted shoreline patrols Sunday morning and observed no visible product along the Delaware River. The Pennsylvania Fish and Boat Commission is monitoring for any impact on fish or aquatic life. Among the chemicals that spilled, butyl acrylate is a potentially flammable colorless liquid with an acrid odor which can cause irritation of the eyes, skin, nose and throat as well as skin inflammation. Methyl methacrylate, sometimes called MMA, is a colorless liquid used in the production of acrylic plastics and resins. The Delaware Valley Early Warning System (EWS) alerted officials to a contamination involving a latex product that spilled along a Delaware River tributary in Bristol Township, Bucks County, Pennsylvania. An estimated 8,100 gallons of solution – half water and half latex polymer – was spilled, Trinseo PLC said. The Pennsylvania Department of Environmental Protection said an "unknown amount" of the spilled product had entered the Delaware River, but fish and wildlife are said to have not been affected. The department is working closely with partners to monitor the spread of the contaminants and will hold the responsible party accountable.