After more than two weeks of breathing noxious fumes that can cause headaches and nausea, residents of the Carson area are now advised to avoid prolonged outdoor exercise at night and early in the morning.
The amount of hydrogen sulfide gas emanating from decaying vegetation and marine life in the Dominguez Canal has exceeded state nuisance thresholds in some places, but is not considered “imminently dangerous”, Los Angeles County public health officials said Tuesday.
Nevertheless, they recommended that people avoid prolonged outdoor activities between 9 p.m. and 8 a.m. and whenever the smell, which has been compared to that of rotten eggs, vomit and farts, is particularly strong.
Companies with a strong odor should run air conditioners for several hours before workers show up, they said.
“The levels noted may cause noticeable discomfort, irritation, or certain asymptomatic non-sensory effects,” LA County public health officials said in a press release. “However, the effects are not expected to be disabling, but should be transient and reversible as exposure decreases or ceases.”
Previously, authorities had recommended people close their windows and doors – even though many don’t have air conditioning – and move temporarily if the smell makes them too sick.
County officials last week announced residents could be reimbursed for air purifiers and hotels. But it could take weeks to get the refunds.
Carson city officials have also instituted a rebate program.
Air quality monitoring stations have been set up at various locations near the canal, with monitoring efforts focused on schools and senior citizen centers, county public health officials said on Tuesday.
Hydrogen sulfide levels were particularly high in the late evening and early morning in areas near the channel, triggering exercise warnings for those times.
After the stench was first reported to the South Coast Air Quality Management District on October 3, it took 12 days for county crews to start treating the flood control channel in order to reduce the odor.
Workers began spraying the flood control channel on Friday with a biodegradable odor neutralizer called Epoleon that will convert hydrogen sulfide into salt.
The odor was expected to wear off within five days of the treatments – or mid-week, officials said.
On Tuesday, workers were installing equipment that will pump millions of tiny oxygen bubbles into the water to prevent further build-up of hydrogen sulfide.
Carson City Council declared the smell a public nuisance last week.
But Representative Nanette BarragÃ¡n (D-San Pedro) criticized the efforts of city and county authorities as being too slow and insufficient to meet the needs of low-income residents, who cannot afford to wait for reimbursement. .
On Monday, she called on Governor Gavin Newsom to declare a state of emergency.
“These residents need direct help, which is why I ask you to declare a state of emergency so that residents can receive direct aid and not be in debt by this event,” she said. written in a letter to Newsom.
In a normal year, stormwater would have washed away more of the underwater vegetation that is currently decomposing. This year, the drought has caused further build-up, officials said.
Below the surface, vegetation was decomposing – and the process may have been sped up by pallets and cardboard thrown upstream, which provided food for the bacteria, according to the county public works department.
County agencies are investigating whether a fire in a pallet yard led to the spill.