Indirect assessment of 4,4'-diphenylmethane diisocyanate (MDI) exposure by evaluation of specific humoral immune responses to MDI conjugated to human serum albumin.
A health hazard evaluation at a facility that manufactured refrigerated tractor trailers (reefers) for the trucking industry was reviewed. The study was conducted by NIOSH and focused on exposures to diisocyanates in the polyurethane foaming areas of the facility, and on the risk of asthma among exposed workers. A two component polyurethane foam system was used to insulate the walls, ceiling, floor, and doors of the reefer. Component-A of this system consisted of 40 to 50% 4,4'-diphenylmethane-diisocyanate (101688) (MDI) and 50 to 60% of MDI based polyisocyanate. Component-B contained a mixture of polyether polyols, surfactants, catalysts, and blowing agents. A cross sectional study was designed to determine whether workers exposed to MDI had respiratory symptoms and pulmonary function decrements consistent with occupational asthma, and whether there was any relationship between the presence of antibodies to MDI/human-serum-albumin (HSA) and a worker's exposure or disease status. The study cohort included 18 workers from the foaming and painting areas of the facility, divided into exposed and nonexposed groups. Six of the nine in the exposed group had elevated immunoglobulin (Ig)-G antibodies specific for the MDI/HSA conjugate. Two were symptomatic and had a decreased forced expiratory volume for one second forced vital capacity ratio indicative of possible asthma. The six with elevated IgG to MDI/HSA also exhibited antibody responses to the other diisocyanate/HSA antigens. None of the MDI exposed workers demonstrated increased diisocyanate specific IgE antibodies when compared to nonexposed workers or to nonexposed laboratory controls. No definitive cases of occupational asthma were documented. The authors conclude that serum concentrations of MDI specific IgG appear to be a moderately sensitive biological marker of MDI exposure, but not an indicator of occupational asthma. Workers with IgG antibodies specific for one diisocyanate/HSA conjugate exhibited cross reactivity to antigens prepared with the other diisocyanates.
Links with this icon indicate that you are leaving the CDC website.
The Centers for Disease Control and Prevention (CDC) cannot attest to the accuracy of a non-federal website.
Linking to a non-federal website does not constitute an endorsement by CDC or any of its employees of the sponsors or the information and products presented on the website.
You will be subject to the destination website's privacy policy when you follow the link.
CDC is not responsible for Section 508 compliance (accessibility) on other federal or private website.
For more information on CDC's web notification policies, see Website Disclaimers.
CDC.gov Privacy Settings
We take your privacy seriously. You can review and change the way we collect information below.
These cookies allow us to count visits and traffic sources so we can measure and improve the performance of our site. They help us to know which pages are the most and least popular and see how visitors move around the site. All information these cookies collect is aggregated and therefore anonymous. If you do not allow these cookies we will not know when you have visited our site, and will not be able to monitor its performance.
Cookies used to make website functionality more relevant to you. These cookies perform functions like remembering presentation options or choices and, in some cases, delivery of web content that based on self-identified area of interests.
Cookies used to track the effectiveness of CDC public health campaigns through clickthrough data.
Cookies used to enable you to share pages and content that you find interesting on CDC.gov through third party social networking and other websites. These cookies may also be used for advertising purposes by these third parties.
Thank you for taking the time to confirm your preferences. If you need to go back and make any changes, you can always do so by going to our Privacy Policy page.