Construction

Burden

Exposure to mineral dusts occurs during many different construction activities, notably abrasive blasting, jack hammering, rock or well drilling, concrete drilling, tuck-pointing, cement finishing, brick and concrete block cutting and sawing, excavating, and highway work. A 2010 study revealed that over 50% of construction workers reported occupational exposure to vapors, gas, dust, or fumes at least twice a week, which was twice as likely as workers from all industries [CPWR 2013]. These activities and subsequent exposures can result in respiratory diseases (e.g., silicosis, asbestosis, chronic obstructive pulmonary disease [COPD], and lung cancer), and reduce a worker’s length and quality of life. In fact, older construction workers are about twice as likely to die of respiratory cancer or non-malignant respiratory disease as their white-collar counterparts, after adjusting for smoking and other confounders [Wang et al. 2016]. Based on the number of deaths among U.S. residents during 1990–1999, construction accounted for 13.4% of all deaths due to silicosis, which was the third largest percentage for any sector [NIOSH 2008a].

Mesothelioma deaths are a marker for previous asbestos exposure, and the construction sector had the highest PMR for mesothelioma deaths in 1999, the last year that industry and occupation was coded from death certificates from many states [NIOSH 2008b]. Construction workers continue to be exposed from previously-installed asbestos containing materials in old buildings that is disturbed by renovation or demolition. An emerging issue potentially affecting construction workers is exposure to noncommercial elongate mineral particles (EMPs) with potential for asbestos-like health effects. These materials can be encountered by disturbing natural deposits during construction activities, or by using materials such as crushed stone products contaminated with EMPs [NIOSH 2011].

Need

There is a need for basic/etiologic research to identify potential health hazards of new and emerging agents such as commercial and non-commercial elongate mineral fibers; and improve understanding of dose-response relationships and use that information to better determine how much of a reduction in exposure is needed to prevent adverse health effects from these fibers. Surveillance research is needed to develop novel approaches for health and hazard surveillance that will improve the ability to track the burden of work-related illnesses associated with mineral dust and commercial and non-commercial elongate mineral fiber exposures.

Intervention research is needed to develop and enhance the performance of technologies such as engineering  controls and personal protective equipment (PPE) to protect against adverse health effects of  commercial and non-commercial elongate mineral fibers. There is also a need to evaluate the effectiveness of interventions and to encourage uptake of safer and healthier designs. Improving continuous personal dust monitors to be lighter and smaller is relevant and important, as well as developing technology to provide real-time assessment of respirable crystalline silica exposure. Development and demonstration of effectiveness of other improved interventions to control exposures (through the use of video exposure monitoring and other technologies) is also important. Finally, translation research is needed to assist construction stakeholders with implementing Occupational Safety and Health Administration requirements and to collect objective data. Additional efforts are needed to transfer findings from this research into influential documents such as guidance and voluntary consensus standards. There is also a need to translate research findings into software products, applications and interactive webpages to make information easily accessible for construction stakeholders.

Burden

Many construction tasks generate complex airborne hazards. Mixed exposures of particular current concern are welding fumes, those associated with abrasive blasting and those associated with the use of emerging advanced materials such as nanomaterials. Abrasive blasting can generate high levels of respirable particles, and their content can vary with abrasive being use and the surface being blasted. Crystalline silica exposure from sandblasting is the best known risk, and lead exposure is also possible when blasting leaded paint from steel bridges. The use of other blasting materials composed of coal or copper slag raises unanswered questions about the content of the resulting dust and its impact on the respiratory health of construction workers.

The potential for certain nanomaterials to cause asbestos-like effects such as mesothelioma is an emerging concern. Nanomaterial exposures have been measured during routine construction tasks, including: weighing, mixing and applying mortar [Dylla and Hassan 2012]; drilling, cutting, and nailing roofing tiles [West et al. 2016]; and spray applying and sanding wood sealant [Cooper et al. 2017]. The NIOSH-funded Center for Construction Research and Training maintains an eLCOSH Nano inventory that has shown numerous applications for engineered nanomaterials in construction, particularly for coatings and paints [CPWR 2014].

Welding is a common construction activity and welding fume exposure is another concern. Exposures often exceed NIOSH Recommended Exposure Limits (RELs) [CPWR 2013]. Welding fume toxicity is of particular concern in confined environments associated with activities like maintenance/repair, construction, and/or mobilization/demobilization of equipment, facilities, and infrastructure. Welders can experience occupational asthma, lung cancer, metal fume fever, and increased susceptibility to pneumonia [HSE 2017].

Need

Workers and contractors need to recognize the hazards posed by these complex exposures, understand the risk factors, and take appropriate precautions. What research is needed varies by agent and exposure. Basic/etiologic research is needed to identify potential health hazards of new and emerging agents such as nanomaterials, advanced manufacturing materials, and abrasive blasting agents. Many of the nanomaterials can be identified through the eLCOSH Nano inventory. There is a need to improve our understanding of dose-response relationships and use that information to determine how much of an exposure reduction is needed to prevent adverse health effects. Better documentation of exposures and health effects in workers exposed to beryllium-containing coal ash or abrasive blasting materials made from coal or copper slag is also needed. Etiologic research (epidemiology and toxicology studies) on the health effects of some types of welding exposures is needed. The relative potency of fumes generated by different welding processes and types of electrodes and base materials is also of interest. Intervention research is needed to improve the existence, performance. and adoption of control technologies, prevention approaches, and interventions for worker exposures to welding fumes (engineering controls, personal protective equipment, etc). An important need for secondary prevention is to develop evidence-based guidelines for construction workers. Research concerning beryllium sensitization and disease in these working populations would be timely and likely to have relevance and impact.