A new study released on April 15, 2015 has drawn further attention to the physical and medical impact of exposure to ambient levels of benzene, toluene, ethylbenzene, and xylene, commonly referred to as "BTEX" chemicals. BTEX chemicals are utilized in hundreds of consumer and industrial products and are commonly found in many popular adhesives, degreasers, detergents, dyes, explosives, fuels, ink, lacquers, pesticides, polishes, resins, rubber cement, and solvents. At present, ethylbenzene is one of the most common chemicals found in children's toys, furniture and furnishings, playground and sporting equipment, and plastic and rubber products. Toluene is frequently used in consumer products such as fuels, paints, and coatings.
The Endocrine Disruption Exchange ("TEDX") and the University of Colorado Boulder study, "New Look at BTEX: Are Ambient Levels a Problem?" reviewed the impact of exposure to ambient levels of BTEX chemicals at levels below reference concentrations which are considered safe levels under EPA regulations. Upon analysis, they concluded that even non-occupational exposure levels to BTEX chemicals may affect hormone levels and contribute to hormone-related health conditions.
Several different types of hormones are affected by exposure to BTEX chemicals, including estrogens, androgens, glucocorticoids, insulin, and serotonin. As a result, the study concluded that exposure to BTEX chemicals affects the endocrine system which acts to regulate the homeostatic processes that contribute to growth and development, immune responses, reproduction, complex behaviors, metabolism, respiration, and aging.
TEDX focused on prenatal and early childhood exposure to analyze the frequency of early disruptions to the developing endocrine system. The study found that ambient level exposures were linked to sperm abnormalities, reduced fetal growth, cardiovascular disease, respiratory dysfunction, asthma, and sensitization to common antigens. Exposure to benzene alone was associated with abnormal sperm production, altered menstrual cycles, spontaneous abortions, and decreased immune cells and antibodies. Finally, the study questioned the safety of chronic low levels of exposure to benzene alternatives, including toluene and zylene.
The study recommended an evaluation of the use of BTEX chemicals in commonly available products going forward. Moreover, the study argued for a general overhaul of how chemicals are presently assessed and regulated at low concentrations.
In response, the EPA announced it will review the study and assess thousands of chemicals and their effect on and risk to the human endocrine system.