Workers at plants in Kenya where lead acid batteries are made and recycled have dangerously high levels of lead in their blood, which puts them at risk for serious health effects, according to a new study published in Environmental Health News.

Researchers found that lead levels in the air far exceed U.S. job safety standards, and that workers had about twice as much lead in their blood as U.S. safety standards allow.

High lead exposures can cause health problems such as blood cell damage, nervous system impairments, kidney problems and cardiovascular disease.

The study sheds light on the health and safety issues at acid battery plants in economically developing countries and suggests workers need better protection against high exposures.

To gain their data, researchers sampled air at several facilities and from different locations within those facilities. They also measured the blood lead levels in the office workers and the production floor workers in the same five areas at both plants.

Concentrations of lead in the air during an 8-hour work shift at both the manufacturing and recycling plants repeatedly exceeded 50 micrograms per cubic meter – the lead level permissible by the OSHA.

In both plants, the average blood lead levels among the workers exceeded the maximum recommended concentration of 30 µg/dL set by the American Conference of Industrial Hygienists. The specific levels varied little among different parts of the production floors in both the recycling and manufacturing plants. Average blood levels were 62.2 µg/dL and 59.5 µg/dL in the respective plants. Levels measured in office workers were 43.4 µg/dL and 41.6 µg/dL, respectively.

The sheer number of batteries made and recycled as well as lax safety controls contribute to the exposures that are 7 to 8 times higher than U.S. workplace limits for air and about twice as high as standards set for blood lead levels.