L. Christine Oliver, MD was our guest on this week’s episode of IAQradio. Dr. Oliver is a physician at Massachusetts General Hospital and an Associate Clinical Professor at Harvard Medical School. Her primary specialty is Occupational and Environmental Medicine. In addition to caring for patients and teaching; she has done research, published and testified before Congress on work related health issues and risks.
Nuggets mined from today’s episode:
While working in her medical residency in an urban hospital she realized that she wanted to get ahead of illness and disease by preventing it from occurring. While she couldn’t positively effect change in lifestyle and what was occurring in homes that caused illness and disease, she focused on occupational causes of illness and disease.
Environmental medicine is growing in recognition and becoming increasing important. Environmental medicine and occupational medicine have merged.
Asbestos, silica, cobalt, tungsten carbide, beryllium, concrete & cement, and VOCs are some of the occupational hazards that she has been involved in.
She has also carried out IAQ evaluations. Buildings which she has investigated and done epidemiological surveys include: office buildings, schools, healthcare facilities, court houses, and residences. While able to locate the areas of concern during walk through inspections, she commonly works with an Industrial Hygienist who is responsible for sampling.
PELs and TLVs are used in industrial settings as guidelines for workplace exposure to specific chemicals or other agents. However, PELs and TLVs were never meant to draw a line between what’s safe and unsafe. Rather they were designed to protect the most vulnerable workers. Exposures below the TLVs and PELs are not necessarily safe. PELs and TLVs are related to workplace exposure in the industrial setting. They don’t translate to nor are they appropriate for offices, health care facilities, schools, and residences. Are factory workers immune to hazardous substances and office workers not immune? The EPA has responsibility for setting exposure guidelines in nonindustrial settings where members of the general population are at risk for exposure. The EPA has lagged behind in fulfilling its responsibilities and, for example,has not established exposure guidelines for mold or VOCs.
There appears to be a genetic predisposition to certain lung diseases. Only 8% of insulation workers exposed to asbestos develop malignant mesothelioma. Siblings in exposed families have developed asbestos-related disease, including malignant mesothelioma. It’s likely that there are genetic predispositions to many other diseases.
A genetic predisposition doesn’t mean someone will develop disease without exposure. If someone has both the predisposition and exposure, they are more likely to develop the disease. When someone has neither a predisposition nor exposures,they are unlikely to get disease.
Cigarette smoke acts in a supra-additive (greater than additive but less than multiplicative) manner to increase risk for certain exposure-related diseases. For example, cigarette smokers have increased risks for asbestos related cancer compared to non-smokers also exposed to asbestos. Silica + smoking has a supra-additive risk for lung cancer. Important associations between smoking and workplace exposure to vapors, gases, dust, fumes act supra-additively to increase risk for COPD, a disease that occurs much more commonly than asbestos- or silica-related disease.
COPD is chronic, progressive, irreversible respiratory disease that involves diminished inspiratory and expiratory capacity of the lungs. Those with COPD have difficulty getting air out of lungs due to obstruction. In the case of asthma, obstruction is usually reversible with bronchodilators. With COPD, the obstruction is fixed. COPD has been categorized as either chronic bronchitis or emphysematous. Emphysema is destruction of alveoli in the lung tissue.
Remediation Worker Exposures
Dr. Oliver has treated construction workers who became ill and/or developed asthma after removing mold -contaminated materials in a water damaged building. She opines that education of workers about the risks is the most important thing. What risks are present? How can workers protect themselves against adverse health effects? How can workers prevent taking risks home?
Asthma has been known to develop in children who were exposure to mold during infancy. Wet buildings are known to aggravate preexisting health conditions. In addition to mold, bacteria, dust mites, and mVOCs are often found in wet buildings. Adults living in chronically damp buildings have developed asthma, hypersensitivity pneumonitis, chronic sinusitis, and laryngitis.
Many irritants and sensitizers such as diesel fumes, chemical spills/releases, fragrances, air fresheners, diisocyanates, aerosol cleaning products, second hand smoke, etc. can trigger asthma. Hot humid and cold weather can also trigger asthma symptoms. Professional cleaners have increased risk for asthma. Non-professional cleaners at home have developed diagnosed asthma with 4 or more exposures to aerosol cleaning agents per week and wheezing with only 1 exposure per week.
Increased use of chemicals, wet buildings, poor HVAC design and maintenance, insufficient fresh air, “hygiene hypothesis”, climate change, virulent pollen, hand sanitizers and quaternary ammonium compounds all contribute to the rise of asthma in the USA.
Cites work of Dr. Anne Steinemann, PhD (http://www.drsteinemann.com/
) on fragrances. Both are advocates for fragrance free policy in offices.
Multiple Chemical Sensitivity
Multiple Chemical Sensitivity (MCS) is a spectrum from mild chemical sensitivity to severe impairment. There are five consensus criteria used to define MCS: a chronic condition  with symptoms that recur reproducibly,  that occur in response to low levels of exposure, that occur following exposure to multiple unrelated chemicals, and  that improve or resolve when incitants are removed. These are still unrefuted in published literature. There is a 6th criterion that we now propose adding – i.e., requiring that symptoms occur in multiple organ systems. https://www.ncbi.nlm.nih.gov/pubmed/00010444033
There are no medical tests to diagnose MCS. There is a predominance of MCS among women who are often high achievers such as nurses, teachers, architects. 30%-33% of the US population consider themselves to be sensitive to chemicals. Medically diagnosed MCS is 2.5%-3% of the urban population. Neurologic, respiratory, cognitive, gastrointestinal, and neuromuscular are among the symptoms she sees in her patients. She is careful not to dismiss valid protective responses to exposure situations as Pavlovian. MCS has a devastating effect on mental health (isolation).
MCS maybe have genetic predisposition. Acceptable studies to sort this out haven’t been done. High level exposures have been shown to cause disruptive changes in the mucous membranes of the nose (cited work by William J. Meggs, M.D., PhD), creating a situation analogous to RADS (reactive airway dysfunction syndrome) in occupational asthma.
Rather than focus on occupational illness and disease in isolation, it is important to broaden the focus to include the relationship with public health.
Z-Man signing off
What is the etymology of the word allergy?
From the Greek “allos” meaning changed or altered state and “ergon” meaning reaction or reactivity.