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Melissa A McDiarmid

Publications and source records attributed to Melissa A McDiarmid.

16 recordsLinked to original sources

Preconception brief: occupational/environmental exposures.

In the last decade, more than half of U.S. children were born to working mothers and 65% of working men and women were of reproductive age. In 2004 more than 28 million women age 18-44 were employed full time. This implies the need for clinicians to possess an awareness about the impact of work on the health of their patients and their future offspring. Most chemicals in the workplace have not been evaluated for reproductive toxicity, and where exposure limits do exist, they were generally not designed to mitigate reproductive risk. Therefore, many toxicants with unambiguous reproductive and developmental effects are still in regular commercial or therapeutic use and thus present exposure potential to workers. Examples of these include heavy metals, (lead, cadmium), organic solvents (glycol ethers, percholoroethylene), pesticides and herbicides (ethylene dibromide) and sterilants, anesthetic gases and anti-cancer drugs used in healthcare. Surprisingly, many of these reproductive toxicants are well represented in traditional employment sectors of women, such as healthcare and cosmetology. Environmental exposures also figure prominently in evaluating a woman's health risk and that to a pregnancy. Food and water quality and pesticide and solvent usage are increasingly topics raised by women and men contemplating pregnancy. The microenvironment of a woman, such as her choices of hobbies and leisure time activities also come into play. Caregivers must be aware of their patients' potential environmental and workplace exposures and weigh any risk of exposure in the context of the time-dependent window of reproductive susceptibility. This will allow informed decision-making about the need for changes in behavior, diet, hobbies or the need for added protections on the job or alternative duty assignment. Examples of such environmental and occupational history elements will be presented together with counseling strategies for the clinician.

Adolescent↗

Depleted uranium exposure and health effects in Gulf War veterans.

Health effects stemming from depleted uranium (DU) exposure in a cohort of Gulf War veterans who were in or on US Army vehicles hit by friendly fire involving DU munitions are being carefully monitored through the Baltimore Veterans Affairs (VA) DU Follow-Up Program initiated in 1993. DU exposure in this cohort has been directly measured using inductively coupled plasma-mass spectrometer (ICP-MS) isotopic analysis for DU in urine specimens. Soldiers with embedded DU fragments continue to excrete elevated concentrations of U in their urine, documenting ongoing systemic exposure to U released from their fragments. Biennial surveillance visits provide a detailed health assessment that includes basic clinical measures and surveillance for early changes in kidney function, an expected target organ for U. Tests also include measurements of genotoxicity and neuroendocrine, neurocognitive and reproductive function. With the exception of the elevated urine U excretion, no clinically significant expected U-related health effects have been identified to date. Subtle changes in renal function and genotoxicity markers in veterans with urine U concentrations greater than 0.1 microg(-1) creatinine, however, indicate the need for continued surveillance of these DU-exposed veterans.

Gulf War↗

Chemical hazards in health care: high hazard, high risk, but low protection.

It is counter-intuitive that the healthcare industry, whose mission is the care of the sick, is itself a "high-hazard" industry for the workers it employs. Possessing every hazard class, with chemical agents in the form of pharmaceuticals, sterilants, and germicidals in frequent use, this industry sector consistently demonstrates poor injury and illness statistics, among the highest in the United States, and in the European Union (EU), 34% higher than the average work-related accident rate. In both the United States and the EU, about 10% of all workers are employed in the healthcare sector, and in developing countries as well, forecasts for the increasing need of healthcare workers (HCW) suggests a large population at potential risk of health harm. The explosion of technology growth in the healthcare sector, most obvious in pharmaceutical applications, has not been accompanied by a stepped up safety program in hospitals. Where there is hazard recognition, the remedies are often voluntary, and often poorly enforced. The wrong assumption that this industry would police itself, given its presumed knowledge base, has also been found wanting. The healthcare industry is also a significant waste generator threatening the natural environment with chemical and infectious waste and products of incineration. The ILO has recommended that occupational health goals for industrial nations focus on the hazards of new technology of which pharma and biopharma products are the leaders. This unchecked growth cannot continue without a parallel commitment to the health and safety of workers encountering these "high tech" hazards. Simple strategies to improve the present state include: (a) recognizing healthcare as a "high-hazard" employment sector; (b) fortifying voluntary safety guidelines to the level of enforceable regulation; (c) "potent" inspections; (d) treating hazardous pharmaceuticals like the chemical toxicants they are; and (e) protecting HCWs at least as well as workers in other high-hazard sectors.

Delivery of Health Care↗

Biological monitoring and surveillance results of Gulf War I veterans exposed to depleted uranium.

OBJECTIVE: To relate medical surveillance outcomes to uranium biomonitoring results in a group of depleted uranium (DU)-exposed, Gulf War I veterans. METHODS: Thirty-two veterans of Gulf War I who were victims of 'friendly fire' involving DU weapons, in whom exposure assessment can accurately be measured, had urine uranium concentrations determined using ICP-MS technology. Clinical laboratory parameters were measured and related to urine uranium concentrations. Data were examined by stratifying the cohort into a low U group, <0.10 mug/g creatinine versus a high U group, >/=0.10 mug/g creatinine and assessing differences between groups. RESULTS: Over a decade after first exposure, soldiers possessing embedded DU fragments continue to excrete elevated concentrations of uranium in urine. No clinically significant uranium related health effects were observed in blood count, blood chemistries including renal markers, neuropsychological measures, and semen quality or genotoxicity measures. Markers of early changes in renal glomerular and tubular function were not statistically different between groups; however, genotoxicity measures continue to show subtle, mixed results. CONCLUSION: Persistent urine uranium elevations continue to be observed more than 12 years since first exposure. Despite this, renal and other clinical abnormalities were not observed, likely due to the 'relatively' low uranium burden in this cohort compared to historical uranium-exposed occupational groups. Continuing surveillance is indicated, however, due to the on-going nature of the exposure. These results are an important finding in light of the on-going controversy regarding health effects observed in soldiers of the Gulf War and other conflicts, whose uranium exposure assessment is unable to be accurately determined.

Adolescent↗

Uranium analysis in urine by inductively coupled plasma dynamic reaction cell mass spectrometry.

Urine uranium concentrations are the best biological indicator for identifying exposure to depleted uranium (DU). Internal exposure to DU causes an increased amount of urine uranium and a decreased ratio of 235U/238U in urine samples, resulting in measurements that vary between 0.00725 and 0.002 (i.e., natural and depleted uranium's 235U/238U ratios, respectively). A method based on inductively coupled plasma dynamic reaction cell mass spectrometry (ICP-DRC-MS) was utilized to identify DU in urine by measuring the quantity of total U and the 235U/238U ratio. The quantitative analysis was achieved using 233U as an internal standard. The analysis was performed both with and without the reaction gas oxygen. The reaction gas converted ionized 235U+ and 238U+ into 235UO2+ (m/z = 267) and 238UO2+ (m/z = 270). This conversion was determined to be over 90% efficient. A polyatomic interference at m/z 234.8 was successfully removed from the 235U signal under either DRC operating conditions (with or without oxygen as a reaction gas). The method was validated with 15 urine samples of known uranium compositions. The method detection limit for quantification was determined to be 0.1 pg U mL(-1) urine and an average coefficient of variation (CV) of 1-2% within the sample measurements. The method detection limit for determining 235U/238U ratio was 3.0 pg U mL(-1) urine. An additional 21 patient samples were analyzed with no information about medical history. The measured 235U/238U ratio within the urine samples correctly identified the presence or absence of internal DU exposure in all 21 patients.

Humans↗

Occupational exposures and reproductive health: 2003 Teratology Society Meeting Symposium summary.

Assuring reproductive health in the workplace challenges researchers, occupational safety and health practitioners, and clinicians. Most chemicals in the workplace have not been evaluated for reproductive toxicity. Although occupational exposure limits are established to protect 'nearly all' workers, there is little research that characterizes reproductive hazards. For researchers, improvements in epidemiologic design and exposure assessment methods are needed to conduct adequate reproductive studies. Occupational safety and health programs' qualitative and quantitative evaluations of the workplace for reproductive hazards may differ from standardized approaches used for other occupational hazards in that estimates of exposure intensity must be considered in the context of the time-dependent windows of reproductive susceptibility. Clinicians and counselors should place the risk estimate into context by emphasizing the limitations of the available knowledge and the qualitative nature of the exposure estimates, as well as what is known about other non-occupational risk factors for adverse outcomes. This will allow informed decision-making about the need for added protections or alternative duty assignment when a hazard cannot be eliminated. These policies should preserve a worker's income, benefits, and seniority. Applying hazard control technologies and hazard communication training can minimize a worker's risk. Chemical reproductive hazard training is required for workers by the Occupational Safety and Health Administration's Hazard Communication Standard. The National Institute for Occupational Safety and Health (NIOSH) has formed a National Occupational Research Agenda Team to promote communication and partnering among reproductive toxicologists, clinicians and epidemiologists, to improve reproductive hazard exposure assessment and management, and to encourage needed research.

Female↗

Prediction of renal concentrations of depleted uranium and radiation dose in Gulf War veterans with embedded shrapnel.

Mobilization of uranium (U) from embedded depleted uranium (DU) metal fragments in Gulf War veterans presents a unique exposure scenario for this radioactive and nephrotoxic metal. In a cohort of exposed veterans, urine U concentrations measured every two years since 1993 persistently range from 10 to over 500 times normal levels, indicating that embedded DU fragments give rise to chronic, systemic exposure to U. Health effects of this exposure are not fully known, but clinical surveillance of these soldiers continues in light of animal studies showing that U released from implanted DU pellets results in tissue accumulation of U. The biokinetic model for uranium recommended by the International Commission on Radiological Protection was used to predict kidney U concentrations and tissue radiation doses in veterans with DU shrapnel based on their urine U excretion. Results suggest that kidney U concentrations in some individuals reached their peak within six years after the war, while in others, concentrations continue to increase and are approaching 1 ppm after 10 y. These results are consistent with urine biomarker tests of renal proximal tubular cell function and cytotoxicity which have shown elevated mean urinary protein excretion indicative of functional effects in veterans with high urine U concentrations (> or =0.10 microg g(-1) creatinine). Predicted lifetime effective radiation dose from DU released to the blood for the highest exposed individual in this cohort was substantially less than the National Council on Radiation Protection (NCRP) limit for occupational exposure. These results provide further support for current health protection guidelines for DU, which are based on the metal's chemical rather than its radiological toxicity. In light of the potential for continued accumulation of U in the kidney to concentrations approaching the traditional guidance level of 3 ppm U, these results indicate the need for continued surveillance of this population for evidence of developing renal dysfunction.

Biomarkers↗

Organizational safety culture/climate and worker compliance with hazardous drug guidelines: lessons from the blood-borne pathogen experience.

BACKGROUND: The health risks posed to health care workers (HCW) handling antineoplastic and other hazardous drugs (HDs) are well established. However, despite nearly 20 years of professional practice standards, compliance with safe handling procedures is poor. METHOD: We present documentation of undercompliance with recommended safety procedures for HDs. Then, we examine a similar problem, HCW compliance with blood-borne pathogen universal precautions (UP) and its partial solution tied to the strength of a facility's safety culture. Lessons learned here may be applicable to the HD issue. RESULTS: It is proposed that analyzing a facility's safety culture may enlarge our understanding of the barriers contributing to HD under-compliance and suggest strategies to improve it. CONCLUSION: The Safety Culture paradigm offers many targets for intervention to enhance and promote worker compliance with safe HD handling practices thus mitigating internal exposure.

Blood-Borne Pathogens↗

Health effects of depleted uranium on exposed Gulf War veterans: a 10-year follow-up.

Medical surveillance of a group of U.S. Gulf War veterans who were victims of depleted uranium (DU) "friendly fire" has been carried out since the early 1990s. Findings to date reveal a persistent elevation of urine uranium, more than 10 yr after exposure, in those veterans with retained shrapnel fragments. The excretion is presumably from ongoing mobilization of DU from fragments oxidizing in situ. Other clinical outcomes related to urine uranium measures have revealed few abnormalities. Renal function is normal despite the kidney's expected involvement as the "critical" target organ of uranium toxicity. Subtle perturbations in some proximal tubular parameters may suggest early although not clinically significant effects of uranium exposure. A mixed picture of genotoxic outcomes is also observed, including an association of hypoxanthine-guanine phosphoribosyl transferase (HPRT) mutation frequency with high urine uranium levels. Findings observed in this chronically exposed cohort offer guidance for predicting future health effects in other potentially exposed populations and provide helpful data for hazard communication for future deployed personnel.

Adult↗

Biologic monitoring for urinary uranium in gulf war I veterans.

Biologic monitoring for total uranium in urine of Gulf War I veterans concerned about past exposure to depleted uranium (DU) has been offered by the Departments of Veterans Affairs and Defense since the late 1990's. DU, a component of U.S. munitions and tank armor, was first used during that conflict. Two hundred and twenty-seven veterans submitted samples for analysis from January 2000 through December 2002, which included a 24-h urine sample for determination of total urinary uranium concentration and completed questionnaires describing their wartime exposure experiences. Thirty questionnaire items characterizing DU exposure opportunities were collapsed into 19 exposure categories. Urine uranium (U) results were stratified into low and high uranium groups with 0.05 microg U g creatinine as the cut point. Exposure scenarios in the high and low uranium groups were similar in frequency and type with only the presence of retained shrapnel being predictive of a high urine uranium value, as found in the first phase of this surveillance of 169 veterans performed prior to 2000. Twenty-two veterans exhibited U levels in the high range. Isotopic analysis, available for 21 of these 22, revealed that all but three of these samples contained natural and not depleted uranium. These three participants had retained DU shrapnel as a result of their past injuries. Thus, even with an enlarged cohort, elevated urine uranium values in the absence of retained DU fragments are unlikely. The utility of isotopic analysis to more fully characterize uranium biomonitoring results is also demonstrated.

Body Burden↗

Terrorism-preparedness training for non-clinical hospital workers: tailoring content and presentation to meet workers' needs.

Clinicians have been the primary focus of health care worker training in response to the 2001 terrorist and anthrax attacks. However, many nonclinical hospital workers also are critical in providing medical care during any large-scale emergency. We designed a training program, guided by focus groups, to provide them with information to recognize unusual events and to protect themselves. We compared four different training methods: workbook, video, lecture, and a small-group discussion. One hundred and ninety-one workers participated. After the training, they were more confident in their employer's preparedness to respond to a terrorist attack but specific knowledge did not change substantially. Fortunately, the self-directed workbook (the more economical and least disruptive method) was as effective as the other methods. Our experience may be useful to others who are planning terrorism-preparedness training programs.

Adult↗

Using the hierarchy of control technologies to improve healthcare facility infection control: lessons from severe acute respiratory syndrome.

Health care facilities need to review their infection control plans to prepare for the possible resurgence of severe acute respiratory syndrome, other emerging pathogens, familiar infectious agents such as tuberculosis and influenza, and bioterrorist threats. This article describes the classic "hierarchy of control technologies" that was successfully used by occupational and environmental medicine professionals to protect workers from illness and death during the resurgence of tuberculosis in the 1990s. Also discussed are related guidelines from building and equipment professional organizations and novel infection control techniques used successfully by various hospitals in Asia, Canada, and the United States during the 2003 severe acute respiratory syndrome epidemic. Taken together, they suggest a framework upon which a comprehensive infection control plan can be crafted to prevent the spread of deadly infectious agents to health care workers (clinicians and paraprofessionals), uninfected patients and visitors.

Disaster Planning↗

Emergency medicine tools to manage smallpox (vaccinia) vaccination complications: clinical practice guideline and policies and procedures.

In December 2002, the federal government began a program to immunize approximately 500000 civilian public health and health care workers with smallpox (vaccinia) vaccine as a part of our pre-event defense against bioterrorism. First responders will likely follow, and the general US population might be offered vaccination in the next 1 to 2 years. Recent reports that suggest the possible association of the vaccine to adverse cardiac events (including deaths), liability concerns for hospitals, and the availability of compensation for workers with vaccine complications have significantly reduced voluntary participation. Vaccinees might experience robust primary takes or serious adverse events, including viral or even bacterial cellulitides, encephalitis, progressive skin destruction, and other life-threatening complications. With the increasing prevalence of immune suppression from both diseases and immunosuppressive medications, complications might be seen in higher frequency than previously reported. Emergency medicine providers and staff must become familiar with clinical presentations and management of vaccine complications. In addition, policies and procedures must be developed to prevent unimmunized providers from inadvertently contacting the active vaccination sites of their patients and, if the providers themselves have active vaccination sites, to protect their patients and their own families.

Antiviral Agents↗

Health effects and biological monitoring results of Gulf War veterans exposed to depleted uranium.

A small group of Gulf War veterans have retained fragments of depleted uranium (DU) shrapnel, the long-term health consequences of which are undetermined. We evaluated the clinical health effects of DU exposure in Gulf War veterans compared with nonexposed Gulf War veterans. History and follow-up medical examinations were performed on 29 exposed veterans and 38 nonexposed veterans. Outcome measures used were urinary uranium determinations, clinical laboratory values, and psychiatric and neurocognitive assessment. Gulf War veterans with retained DU metal shrapnel fragments were found to be still excreting elevated levels of urinary uranium 7 years after first exposure to DU (range for exposed individuals is 0.01-30.7 micrograms/g creatinine vs. 0.01-0.05 microgram/g creatinine in the nonexposed). The persistence of the elevated urine uranium suggests ongoing mobilization of uranium from a storage depot, resulting in chronic systemic exposure. Adverse effects in the kidney, a presumed target organ, were not seen at the time of the study; however, other subtle effects were observed in the reproductive and central nervous systems of the DU-exposed veterans.

Humans↗

Preventing occupational exposures to antineoplastic drugs in health care settings.

The toxicity of antineoplastic drugs has been well known since they were introduced in the 1940s. Because most antineoplastic drugs are nonselective in their mechanism of action, they affect noncancerous as well as cancerous cells, resulting in well-documented side effects. During the 1970s, evidence came to light indicating health care workers may be at risk of harmful effects from antineoplastic drugs as a result of occupational exposure. Since that time, reports from several countries have documented drug contamination of the workplace, identified drugs in the urine of health care workers, and measured genotoxic responses in workers. Evidence also exists of teratogenic and adverse reproductive outcomes and increased cancers in health care workers. During the past 30 years, professional organizations and government agencies have developed guidelines to protect health care workers from adverse effects from occupational exposure to antineoplastic drugs. Although many safety provisions were advanced to reduce worker exposure in the 1980s, recent studies have shown that workers continue to be exposed to these drugs despite safety policy improvements. In 2004, the National Institute for Occupational Safety and Health (NIOSH) published an alert reviewing the most recent information available and promoting a program of safe handling during their use.

Antineoplastic Agents↗