Something is in the South County air.
Two South Bay cities are among the worst in California when it comes to pollution, according to statistics released this summer by the state’s Office of Environmental Health Hazard Assessment.
A CalEnviroScreen study shows that the part of Chula Vista within the 91911 zip code — and National City’s 91950 zip code — are among the top 10 percent of zip codes statewide for combined impacts of pollution and population vulnerabilities. The 91911 area covers Hilltop and part of Olympic Parkway.
The CalEnviroScreen study reports that the 91911 area of Chula Vista scored the highest in pollutants of groundwater contamination at 89.98 percent.
Chula Vista was graded at 72.58 percent in diesel pollution, and is in the 67 percentile for overall particulate matter in air, according to the data.
Diesel is the exhaust produced by diesel engines, while particulate matter is any small particles in the air that are small enough to breathe.
The county’s second largest city recorded a 77.9 percent mark for traffic density and was high on hazardous waste at 89.98 percent. Hazardous waste includes liquids or solvents labeled toxic, corrosive or flammable.
The elevated figures in groundwater and hazardous waste contamination are what pushed the 91911 area to be ranked highly statewide for combined impacts of pollution and population vulnerabilities, said Joy Williams, research director for the National City-based Environmental Health Coalition.
Manuel Medrano, a recycling specialist with the city of Chula Vista, said the city encourages residents to help curb hazardous waste.
“The city of Chula Vista encourages the reduction of hazardous materials exposure by encouraging its residents to only buy what they need and avoid large purchases of household toxics that could result in many leftover materials that could be stored incorrectly and cause a spill or be improperly disposed,” he said in an e-mail.
Chula Vista also offers a hazardous waste disposal facility at 1800 Maxwell Road.
Statistics for the 91950 zip code showed National City was near the top in California when it came to pollution levels.
“National City is worse than 90 percent of the rest of the state in the things that this model scores,” Williams said.
National City also scored the highest amount of pollution in groundwater threats, listed on the report at 98.51 percent.
National City’s pollution of diesel is in the 84.85 percent bracket.