T. Morris, Ohio BWC, Employer Management Services, Cincinnati, OH.
Herbal medicines (HM) are a multibillion dollar a year U.S. industry; worldwide sales are estimated at $60 billion. Included in this category are traditional Chinese or Indian medicines, other ethnic medicinal preparations, and individual medicinal herbs such as St. John’s wort or echinacea. An estimated 42% of the U. S. adult population (94 million people) has used HMs; the percentages are higher in Europe, Australia, and Asia. In general, HMs have a long history of few adverse effects, but the actual safety and efficacy of these products are not adequately known. In the United States, HMs are exempt from the FDA oversight prescription drugs receive and are classified as a dietary supplement by the DSHE Act of 1994. HM use in the occupational setting is of concern for many reasons. The large number of users puts many of them in our workplaces every day. Many consider HMs to be natural, safe, and effective, and they may not associate an adverse effect with its use. HM use is rarely reported to health care providers or health and safety professionals. Active compound levels (when known) can vary considerably. HMs can be directly toxic. Some can induce, inhibit, or compete for cytochrome P-450, affecting how industrial solvents and prescription drugs are metabolized. Some contain metals (As, Cd, Pb, Hg) or adulterants, including therapeutic levels of prescription medicines leading to toxicity, accidents, adverse drug reactions, or a positive drug test. HM users can present with the classic symptoms of an occupational disease (e. g., lead poisoning) that are missed because there is no occupational toxicant exposure history, delaying the diagnosis and treatment and wasting valuable time and resources. HMs will be introduced to heighten health and safety professionals’ awareness of this overlooked area of self-medication and its potential for adverse employee impact.
A. Fedorowicz, T. Michette, CDC/NIOSH, Morgantown, WV.
Estimates indicate that more than 13 million workers in the United States are potentially exposed to chemicals that can be absorbed through the skin. Contact dermatitis from workplace chemicals accounts for 10–15% of all occupational illnesses at an estimated annual cost of at least $1 billion. Allergic contact dermatitis is considered to be a significant factor for the development of eczema in 48% of the cases for women and in 40% of the cases for men. Access to information that could be used for developing skin exposure limits is very important for the industrial hygienist. Most of the experimental methods, which have been proposed to assess the skin sensitization potential of a chemical, produce results using a binary scale that cannot be easily used to develop skin exposure limits. The dose-response data of the murine Local Lymph Node Assay (LLNA) can be used to produce a standardized continuous scale in the quantitative assessment of skin sensitization. A computer application containing LLNA-tested substances with data for more than 350 chemicals has been developed. The availability of continuous data allows them to be applied in the process of risk assessment and for recommendation of skin exposure limits. These recommendations will be based on potency, in contrast to current approaches that often do not differentiate between weak and extreme skin sensitizers, thus permitting the latter to be present in concentrations that can still cause health problems. In addition, the inclusion of several models for calculating the skin permeation coefficient provides an additional tool for risk assessment. The database can be used to search for LLNA-tested substances that structurally resemble the entry chemical. The results of this search might be used in qualitative assessment of skin sensitization activity of untested chemicals.
S. Czerczak, A. Palaszewska, Nofer Institute of Occupational Medicine, Lodz, Poland.
The increasing incidence of occupational diseases among workers exposed to
different toxic agents, including carcinogens, has become a matter of interest
in the course of continuing industrial development. Among steps taken to reduce
the discussed morbidity the proper restrictions and employers duties were
implemented in the legal system. ILO Convention No. 139 (Occupational Cancer
Convention) resulted in implementation of suitable regulations within the
European Union countries. Polish regulation of the Minister of Health of
December 1, 2004, concerning carcinogenic or mutagenic substances, preparations,
agents, or technological processes in working environments containing the
registry of over 800
carcinogens and mutagens, similar to the previous legislation in this field,
specifies duties of the employers hiring the workers in the exposure to
carcinogens. Among those the employer is not only obliged to diagnose the
working environment in terms of carcinogenic agents occurrence and potential
exposure levels but also to assess employees’ health risks resulting from
occupational exposure. To facilitate assessing health risk from carcinogens to
employers and relevant labor safety services, the Nofer Institute of
Occupational Medicine prepared guidelines for assessing health risk from
carcinogens. Guidelines are being prepared on the basis of the latest studies
results that have been described in the international scientific journals. The
scope of the guidelines comprises data concerning physicochemical properties,
occurrence, usage, and exposure to the substance, its biological activity
including absorption, acute and chronic toxicity, carcinogenicity, mutagenicity,
and reprotoxicity in humans and experimental animals, and moreover qualitative
and quantitative risk assessment of the neoplastic changes development and
occupational exposure limit values in force in Poland and other countries. It
should be noted that the quantitative risk assessment mentioned above enables
estimation of the potential health risk with reference to the specified exposure
levels of particular carcinogenic agents within specific working conditions. An
example of quantitative risk assessment for 2,4-dinitrotoluene is to be
presented.
A. Maier, B. Gadagbui, Toxicology Excellence for Risk Assessment, Cincinnati, OH; A. Weinrich, U.S. EPA, Cincinnati, OH; C. Geraci, NIOSH, Cincinnati, OH.
Immediately Dangerous to Life or Health (IDLH) concentrations have a long history of use in industrial settings in defining work practice and respiratory protection requirements for entry into potential high exposure environments. We explored approaches for extrapolating from acute toxicity data in animals to estimate human effect thresholds that might serve as the basis for deriving an IDLH value. Based on our analysis we propose updated default factors for extrapolating to an IDLH value from either an LC50 (the concentration estimated to cause a 50% mortality rate in an acute toxicity study) or an animal lethality threshold (commonly estimated as an animal LCLO, LC10, etc.) when more precise data are unavailable. We hypothesized that potent irritants may have a greater LC50/human serious effect threshold ratio than other chemicals. Our results were mixed with a significant mode of action effect observed for a subset of 20 chemicals, but not in a broader analysis of current IDLH values. Approaches for using endpoints other than lethality from acute toxicity studies also were investigated. We found that for many chemicals, the application of quantitative concentration-response approaches is hampered by typical study designs. One type of acute animal toxicity study result that often is used as a basis for deriving an IDLH concentration for irritants is an RD50 (a concentration that reduces respiratory rate in a standardized rodent test by 50%). We evaluated ratios of RD50 values to current human-effect based IDLH concentrations and, based on the distribution of these ratios, propose applying a default factor to these values to derive an IDLH concentration. Overall, this work further enhances the transparency of the underlying rationale for the default methods used to derive IDLH concentrations.
A. Madl, E. Donovan, D. Paustenbach, ChemRisk Inc., San Francisco, CA; M. Kelsh, Exponent, Menlo Park, CA.
The current Occupational Exposure Limit (OEL) for beryllium was believed to be protective against chronic beryllium disease (CBD) until studies in the mid-1980s began using newer medical diagnostic techniques that identified beryllium sensitization (BeS) and subclinical disease in the absence of physical symptoms. The objective of this study was to review all available epidemiologic studies of beryllium workers to assess whether any patterns are observed for exposure indices, job categories, manufacturing processes, chemical forms of beryllium (e.g., beryllium oxide, metal, and alloy), and the prevalence of CBD and BeS. In addition, the influence of particle size and different exposure metrics on CBD and BeS was evaluated. Despite considerable variation in study findings, several patterns are apparent. First, the prevalence of CBD and BeS was greatest among workers involved with machining or grinding of beryllium oxide and metal. Second, no cases of CBD have been reported among workers with exclusive exposure to mining or processing of beryllium ore. Third, differences in the prevalence of CBD involving work with different chemical forms of beryllium appear to be dependent on the operation and generation of fine particulate. Fourth, frequency and magnitude of peak concentrations as well as particle size appear to be associated with the prevalence of CBD and BeS. In contrast, mean or median airborne concentrations of beryllium, cumulative dose, and exposure duration have not provided consistent dose-response associations. Fifth, CBD and BeS are observed among workers who are employed in areas where airborne beryllium concentrations are generally greater than 0.2 µg/m3. Based on what has been learned in recent years, increased risk of BeS and CBD is likely derived from a combination of factors such as particle size, chemical form of beryllium, and peak exposure, which are important to consider when setting an OEL for beryllium.
A. Madl, K. Unice, J. Brown, ChemRisk Inc., San Francisco, CA; M. Kolanz, Brush Wellman Inc., Cleveland, OH; M. Kent, Brush Wellman Inc., Elmore, OH.
The current occupational exposure limit (OEL) for beryllium has been in place for more than 50 years and was believed to be protective until medical diagnostic techniques in the 1980s identified beryllium sensitization (BeS) and chronic beryllium disease (CBD) in the absence of physical symptoms. A major challenge in identifying a revised OEL for beryllium is that previous studies have used inconsistent sampling and exposure assessment methodologies and definitions for BeS and CBD. These differences have prevented direct comparisons between studies as well as the identification of a clear exposure-response relationship. Industrial hygiene and health surveillance data from a beryllium metal machining facility were analyzed to assess whether this information provides insight into the exposure-disease relationship for BeS and CBD, which could be useful in identifying an OEL that is protective of worker health. Airborne beryllium concentrations for different job titles were evaluated, historical trends of personal and ambient beryllium levels were compared for pre- and post-engineering control measures (implemented in the 1990s), and average and upper bound exposure estimates were developed for workers identified as BeS or with CBD. This assessment included the analysis of 3,833 personal lapel and 614 general area samples and other new data collected by plant health and safety staff at the facility. Results of this analysis showed that all workers diagnosed with CBD were exposed to beryllium concentrations of 0.2 µg/m3 (95th percentile) or greater. The prevalence of BeS among surveyed workers exposed below a 95th percentile beryllium concentration of 0.2 µg/m3 was consistent with the anticipated background rate of BeS of 1–2%. It was concluded based on this analysis of BeS and CBD workers in a beryllium metal machining plant, concentrations maintained below 0.2 µg/m3 95% of the time will likely prevent BeS and CBD in nearly all beryllium workers.
B. Doney, M. Greskevitch, D. Groce, NIOSH/CDC, Morgantown, WV.
Respiratory illnesses caused by airborne hazards at the workplace can be prevented by adequate control measures. In the absence of adequate engineering and administrative controls, proper respirator selection and use is essential. NIOSH conducted eight focus groups during March–November 2004 arranged by the National Demolition Association. The association represents the majority (approximately 80%) of U.S. demolition work in terms of revenue. The objectives of the focus groups were to identify the types of airborne hazards present at workplaces, control measures used to reduce these hazards, types of respirators used, and barriers impacting respirator use. Participants reported exposures to abrasive blasting agents, arsenic, asbestos, cadmium, carbon monoxide, chlorine, concrete dust and silica, dust from drywall, diesel, and gasoline fuels, fluorine, hydrogen sulfide, lead, man-made mineral fibers, mold, pigeon droppings, PCBs, ionizing radiation, and welding fumes. Engineering control measures included using water sprays, mechanization, longer torches and standing upwind when cutting, local ventilation, enclosed equipment cabs, and scrubbers on diesel-powered front-end loaders for interior work. Respirators were used where the feasible engineering controls could not reduce the exposures below acceptable limits. Barriers to proper respirator use included high ambient temperatures, fogging of full facepiece respirators, difficulty wearing other personal protective equipment with respirators, reduced peripheral vision, difficulty communicating and breathing, cultural differences with non-English speakers, low literacy, high worker turnover, and short duration of employment for laborers. Overall, participants were knowledgeable about and had implemented OSHA respirator program elements. This poster will describe the focus group findings and the current NIOSH education and intervention strategies to overcome the barriers identified. The findings and conclusions in this abstract have not been formally disseminated by NIOSH and should not be construed to represent any agency determination or policy.
H. Yuasa, T. Honda, K. Kimura, H. Emi, K. Nozaki, KOKEN, Saitama, Japan; S. Tanaka, Jumonji University, Tokyo, Japan; S. Grinshpun, University of Cincinnati, Cincinnati, OH.
Compared with negative pressure respirators, a Powered Air Purifying Respirator (PAPR) equipped with a battery-operated blower provides several advantages with respect to the human protection against contaminated air. It enhances the protection characteristics and lowers the inhalation resistance because the forced air always maintains a pressure above the ambient air pressure level inside the facepiece. Most PAPRs, however, are designed only to maintain a large amount of air blowing that corresponds to the peak inhalation flow of wearers in operation. This necessitates frequent filter replacement resulting in high running costs and causes other problems associated with high exhalation resistance and other factors. In order to solve these problems, we have developed a new PAPR with the built-in Breath-Synchronized Flow System (BSFS-PAPR) that supplies the necessary amount of air on wearer’s inspiration at once and reduces the air supply at the expiration. The BSFS is a small electronic module that allows the real-time detection of the wearer’s respiration basis and controlling the air volume supplied from the blower fan. The BSFS-PAPR continuously maintains a positive pressure inside the facepiece when tested with a breathing machine operated at 24 respirations per minute (volumetric rate = 40 liters per minute), and demonstrates high synchronous performance, even for shallow respiration. Furthermore, it can provide a superior performance by reducing the exhalation resistance and help avoid wasting of filters and battery capacity compared with the traditional continuous flow PAPRs (CF-PAPRs). This presentation communicates the evaluation data on the BSFS-PAPRs’ synchronous performance. The authors also discuss the protection data obtained with human subjects as well as the results of the comparative study involved with the traditional CF-PAPRs.
C. Chen, S. Huang, C. Chang, Institute of Occupational Safety and Health, Council of Labor, Taiwan, Taipei, Taiwan Republic of China.
This study presents the experimental results of penetration of aerosol particles with diameters between 4.5 nm and 10 µm through fibrous filters. The TSI 3080 electrostatic classifier equipped with nano or long differential mobility analyzer and the TSI 3321 aerodynamic particle sizer were used to measure nanometer, submicron, and micron-size particles. NaCl aerosol particles were generated by using spray-drying methods. To eliminate electrostatic charges, filters were dipped in isopropanol for five minutes and allowed to dry. These dipped filters, along with controls of each filter type, were then tested to determine the aerosol penetrations in the size range of 4.5 nm to 10 µm. The experimental results demonstrated that almost all particles with sizes below 10 nm or exceeding 5 µm were collected in the filters, and the filter charges did not significantly affect the penetration values. The results also suggested that there is no thermal rebound of particles in the size range down to 4.5 nm in fibrous filters.
M. Akram, Columbia University, New York,, NY; S. Awan, Center for the Improvement of Working Conditions and Environment, Government of Punjab, Lahore, Pakistan; N. Ahmad, University of Punjab, Lahore, Punjab, Pakistan.
Carpet weaving, an important handicraft industry in rural areas of Pakistan, is very labor-intensive. About 65% of the production cost is labor charges. To reduce cost, use of children as carpet weavers is very common in rural areas. Although the law prohibits employing children under the age of 14 in carpet weaving, lack of enforcement, exemption of home-based industry, and high poverty have made it a common practice. This study was undertaken to assess the health hazards faced by carpet-weaving children, evaluate various stress factors, and compare health implications of this work. The results show that musculoskeletal disorders (MSDs) are most common in these workers. Bending knees, carpal tunnel syndrome (CTS), low back pain, and pain in the neck and shoulders were widespread. Contrary to some previous studies, however, no evidence of blindness or any effects on eyesight were noted. Based on the performance of Phalen’s maneuver, the evidence of CTS in carpet weavers is reported here for the first time. The most likely cause of CTS may be repetitive use of wrists, fingers, and shoulders for long hours. Female children were more susceptible to MSDs than were males, probably due to malnutrition and lack of physical exercise. Other factors may include poor carpet loom design, improper sitting posture, and lack of training. The large average family size of the carpet-weaving children compared with the control may be due to lack of access to and the use of family planning tools as well as limited recreational facilities. These children were also more likely to suffer from physical abuse and malnutrition. The working children compared with the control reported a remarkably high proportion of backache, joint pain, fatigue, stomachache, and cuts and bruises. Respiratory illnesses and scabies were other noticeable problems, most likely due to poor sanitary conditions and lack of awareness.
S. Czerczak, M. Kupczewska Dobecka, Nofer Institute of Occupational Medicine, Lodz, Poland.
In 2005, The Expert Group of Chemical Agents working at the Nofer Institute of Occupational Medicine in Poland proposed Maximum Admissible Concentrations (MACs) values for 16 harmful chemical agents in the working environment in Poland. Following are the substances and their CAS numbers: sulfuric acid (7664-93-9); hexane acyclic saturated isomers, except n-hexane [2,2-dimethylbutane (75-83-2); 2,3-dimethylbutane (79-29-8); 2-methylpentane (107-83-5); 3-methylpentane (96-14-0)]; desflurane (57041-67-5); chlorobenzene (108-90-7); morpholine (110-91-8); 2-aminoethanole (141-43-5); cyanamide (420-04-2); nitric acid (7697-37-2); pyretrynes (8003-34-7); carbon disulphide (75-15-0); nitrotoluene; all isomers [2-nitrotoluene (88072-2); 3-nitrotoluene (99-08-1); 4-nitrotoluene (99-99-0)]; dinitrotoluene; mixture of isomers (25321-14-6); mesityl oxide (141-79-7); sevoflurane (28523-86-6); isoflurane (26675-46-7); 1-bromopropane (106-94-5). According to the type of biological effects, the following categories of MAC values are used: NDS–MAC(TWA): maximum admissible concentration; NDSCh - MAC(STEL): maximum admissible short-term concentration; NDS-MAC(C): maximum admissible ceiling concentration. To 2005 there are 441 MAC values for chemical substances in Poland (The Ordinance of the Minister of Labor and Social Policy, J. Law 217, item 1833, 2002). Interdepartmental Commission for Maximum Admissible Concentrations and Intensities for Agents Harmful to Health in the Working Environment has appointed the Group of Experts for Chemical Agents, consisting of independent experts in the fields of toxicology, occupational medicine, and occupational hygiene. The experts prepare health-based documentation for recommended exposure limits along with analytical procedures, recommendations with respect to pre-employment and periodical medical examinations, and contraindications to exposure. The proposed MAC values are then subject to evaluation by the Interdepartmental Commission and acceptance by the Minister of Labor and Social Policy. The MAC’s list is published in the Law Gazette. In the Polish system, the MAC values documentation is published quarterly in the publication of the Interdepartmental Commission. The authors show the MAC values and their bases for 16 substances.
M. Kupczewska-Dobecka, S. Czerczak, Nofer Institute of Occupational Medicine, Lodz, Poland.
The substances suspected of the ability to increase their contribution to the overall exposure by dermal absorption, i.e., through mucous membranes, eyes, or as a result of the contact of the skin with vapors or liquids, are denoted by the symbol Sk (danger of cutaneous absorption) in the MAC list in Poland. The symbol for assigning the dangers of cutaneous absorption is not included in Polish law and there is no obligation to do so. The Polish Maximal Allowable Concentration list with symbols Sk is published in the Intersectoral Commission publication “Dangerous Substances in Workplace Environment,” edited by the Central Institute of Labor Protection in Warsaw. The current Polish MAC list contains 441 chemical compounds, of which 144 (34.8%) are denoted by Sk. In 2004 The Group of Experts for Chemical Agents working at the Nofer Institute of Occupational Medicine in Lodz - Poland, established MAC values for 33 chemicals. Thirteen of them are denoted with Sk. The Group of Experts for Chemical Agents in Poland proposes criteria for assigning chemicals in the MAC List in Poland the Sk symbol based on the LD50s value, dermal application studies, significant systemic effects following exposure, physicochemical data required to calculate the flow (solubility, octanol/water partition coefficient, molecular weight). It can be concluded that the dermal dose LD50s determined on experimental animals ought to be adopted as the fundamental criterion for providing a substance with the percutaneous absorption notation in the MAC list. All chemicals with LD50s value below 1,000 mg/kg should be provided with the Sk index in the MAC list. Here, the authors present the bases of skin notation for 13 chemical agents for which MAC values were established in 2004. It is the presentation from the viewpoint of the Group of Experts for Chemical Agents in Poland.
R. Patel, Safe Workplace Inc.,Central Industrial Hygiene Association., Anand, Gujrat, India.
The pollen dust is an unwanted weed found in various places around agriculture farms. This study was carried out in small villages of the Kheda district. The contractual farm workers are actively involved in manual cleaning of unwanted weed, which consists of pollen dust in all seasons. It was found that maximum exposures of pollen dust occur near the water canals supply that is used for agricultural purposes in various farms. The local farmers know this weed as “congress grass” or “carrot grass.” The study was carried out for prevention and control of this nuisance dust that causes various health impairments in farm workers. Thirty-five personal samples were collected from shifts in small-scale farms near breathing zones in all seasons. The pollen is collected in air-sampling devices onto a sticky surface and then the pollen is identified for type and counted under a microscope. It was found that the concentration of pollen dust is higher in winter than in summer and lowest in monsoon. During medical surveillance, adverse symptoms of health found included breathlessness, coughing, and rashes on skin along with cases of asthma in winter and nosebleeds in summer. The proper training was provided for cleaning the weed before the flowering stage. Also, air purifying respirators and other personal protective equipment were provided to the workers.
C. Harrison, U.S.Army, Fort George G. Meade, MD; J. Forsythe, U.S. Army, Fort George G. Meade, MD.
We evaluated the sanitary aspects of 13 military dining facilities that were primarily used one to two days per month, with the goals of promoting health protection through food safety, reducing the occurrence of foodborne illness, and ensuring sanitary compliance. Personnel health, cleanliness, hygienic practices, and handling of food throughout preparation are the keys to determining the operation of a safe food service facility. Visual inspections were used to evaluate such factors as general cleanliness, appropriate utensil and food storage, and presence of rodents and other pests. Rodent activity was further evaluated with the use of an ultraviolet (black) light that, when used in a darkened room, caused proteins (such as in rodent urine) to fluoresce. Refrigeration equipment temperatures were measured with calibrated digital thermometers. Water samples were collected and cultured for presence of bacteria using portable incubators. Ventilation measurements of the range hood were collected with calibrated, heated-wire, digital anemometers. Elucidated potential sanitation hazards included: improper labeling; food maintained at incorrect temperatures; contamination by rodent urine and feces; use of inappropriate flying insect traps; peeled and chipped paint flaking onto food preparation surfaces; toxic materials stored with food, equipment, and utensils; lack of required training for supervisors and employees; and lack of medical review of training records. Corrective measures to address all findings were recommended, and implementation of many of these modifications resulted in meeting the goals stated above.
C. Volkmann, S. Lai, D. Most, L. Zakrzewski, D. Hansmann, B. Israel, Platypus Technologies LLC, Madison, WI.
The analysis of toxic vapor phase chemicals has traditionally been conducted using time-consuming, labor-intensive and expensive analytical procedures. A new technology for the passive monitoring of volatile and semi-volatile vapor phase chemicals has been developed that utilizes chemically functionalized, nanotextured substrates to control the orientation of liquid crystals. The orientation of the liquid crystal is perturbed as airborne contaminants diffuse onto the analytical surface from the surrounding environment, resulting in an alteration in the optical properties of the liquid crystal. This response can be readily seen with the naked eye when viewed through crossed polarizing filters. The sensors are simple to use, provide rapid feedback, are versatile (permitting cumulative exposure on the order of days to weeks), and the results are quantifiable. During use, the sensors do not require human intervention, are resistant to interferring compounds, and can be fabricated to detect multiple target chemicals by alterations to the surface chemistry. In this poster we demonstrate a response (in parts per billion) to one class of toxic semi-volatile airborne agents, namely, organophosphate pesticides. This technology can also be easily adapted to other compounds of interest.
Posted May 30, 2006