Vilà et al., 2021
Vilà, Montserrat, Beaury, Evelyn M., Blumenthal, Dana M., Bradley, Bethany A., Early, Regan, Laginhas, Brittany B., Trillo, Alejandro, Dukes, Jeffrey S., Sorte, Cascade J. B., & Ibáñez, Inés; “Understanding the combined impacts of weeds and climate change on crops;” Environmental Research Letters, 2021, 16(3); DOI: 10.1088/1748-9326/abe14b.
ABSTRACT:
Crops worldwide are simultaneously affected by weeds, which reduce yield, and by climate change, which can negatively or positively affect both crop and weed species. While the individual effects of environmental change and of weeds on crop yield have been assessed, the combined effects have not been broadly characterized. To explore the simultaneous impacts of weeds with changes in climate-related environmental conditions on future food production, we conducted a meta-analysis of 171 observations measuring the individual and combined effects of weeds and elevated CO2, drought or warming on 23 crop species. The combined effect of weeds and environmental change tended to be additive. On average, weeds reduced crop yield by 28%, a value that was not significantly different from the simultaneous effect of weeds and environmental change (27%), due to increased variability when acting together. The negative effect of weeds on crop yield was mitigated by elevated CO2 and warming, but added to the negative effect of drought. The impact of weeds with environmental change was also dependent on the photosynthetic pathway of the weed/crop pair and on crop identity. Native and non-native weeds had similarly negative effects on yield, with or without environmental change. Weed impact with environmental change was also independent of whether the crop was infested with a single or multiple weed species. Since weed impacts remain negative under environmental change, our results highlight the need to evaluate the efficacy of different weed management practices under climate change. Understanding that the effects of environmental change and weeds are, on average, additive brings us closer to developing useful forecasts of future crop performance. FULL TEXT
Schulz et al., 2021
Schulz, R., Bub, S., Petschick, L. L., Stehle, S., & Wolfram, J.; “Applied pesticide toxicity shifts toward plants and invertebrates, even in GM crops;” Science, 2021, 372(6537), 81-84; DOI: 10.1126/science.abe1148.
ABSTRACT:
Pesticide impacts are usually discussed in the context of applied amounts while disregarding the large but environmentally relevant variations in substance-specific toxicity. Here, we systemically interpret changes in the use of 381 pesticides over 25 years by considering 1591 substance-specific acute toxicity threshold values for eight nontarget species groups. We find that the toxicity of applied insecticides to aquatic invertebrates and pollinators has increased considerably—in sharp contrast to the applied amount—and that this increase has been driven by highly toxic pyrethroids and neonicotinoids, respectively. We also report increasing applied toxicity to aquatic invertebrates and pollinators in genetically modified (GM) corn and to terrestrial plants in herbicide-tolerant soybeans since approximately 2010. Our results challenge the claims of a decrease in the environmental impacts of pesticide use. FULL TEXT
Nolan et al., 1984
Nolan, R. J., Rick, D. L., Freshour, N. L., & Saunders, J. H.; “Chlorpyrifos: Pharmacokinetics in human volunteers;” Toxicology and Applied Pharmacology, 1984, 73(1), 8-15; DOI: 10.1016/0041-008x(84)90046-2.
ABSTRACT:
The kinetics of chlorpyrifos, an organophosphorothioate insecticide, and its principal metabolite, 3,5,6-trichloro-2-pyridinol (3,5,6-TCP), were investigated in six healthy male volunteers given a single 0.5 mg/kg po and, 2 or more weeks later, a 0.5 or 5.0 mg/kg dermal dose of chlorpyrifos. No signs or symptoms of toxicity or changes in erythrocyte cholinesterase were observed. Plasma cholinesterase was depressed to 15% of predose levels by the 0.5 mg/kg po dose but was essentially unchanged following the 5.0 mg/kg dermal dose. Blood chlorpyrifos concentrations were extremely low (less than 30 ng/ml), and no unchanged chlorpyrifos was found in the urine following either route of administration. Mean blood 3,5,6-TCP concentrations peaked at 0.93 micrograms/ml 6 hr after ingestion of the oral dose and at 0.063 micrograms/ml 24 hr after the 5.0 mg/kg dermal dose. 3,5,6-TCP was cleared from the blood and eliminated in the urine with a half-life of 27 hr following both the po and dermal doses. An average of 70% of the po dose but less than 3% of the dermal dose was excreted in the urine as 3,5,6-TCP; thus only a small fraction of the dermally applied chlorpyrifos was absorbed. Chlorpyrifos and its principal metabolite were rapidly eliminated and therefore have a low potential to accumulate in man on repeated exposures. Based on these data, blood and/or urinary 3,5,6-TCP concentrations could be used to quantify the amount of chlorpyrifos absorbed under actual use conditions.
Chester, 1993
Chester, G.; “Evaluation of agricultural worker exposure to, and absorption of, pesticides;” Annals of Occupational Hygeine, 1993, 37(5), 509-523; DOI: 10.1093/annhyg/37.5.509.
ABSTRACT:
The evaluation of the occupational exposure of agricultural workers to pesticides is an integral part of the risk assessment for product safety and regulatory purposes. At present, there is no internationally accepted, harmonized approach to this exposure evaluation. This paper reviews the currently available methods for the measurement of exposure to, and absorption of, pesticides by workers involved in their use and in associated agricultural activities. Biological monitoring is recommended as the most precise means of estimating the absorbed dose of a pesticide, particularly if supported by human metabolism and pharmacokinetic data. A ‘whole-body’ sampling method is recommended for the measurement of dermal exposure. For concurrent exposure and biological monitoring a refined ‘whole-body’ method is recommended which involves the use of clothing representing that which workers normally wear under the prevailing conditions. A personal air sampling method is recommended for the measurement of inhalation exposure, to collect the ‘inspirable’ fraction (and/or, where necessary, vapour component) of pesticide. These ambient exposure monitoring methods may be conducted simultaneously with biological monitoring. Guidelines are proposed for the conduct of field studies to evaluate exposure to, and absorption of, pesticides to satisfy the requirements of regulatory authority and other organization
Henderson et al., 1993
Henderson, P. T., Brouwer, D. H., Opdam, J. J., Stevenson, H., & Stouten, J. T.; “Risk assessment for worker exposure to agricultural pesticides: review of a workshop;” Annals of Occupational Hygeine, 1993, 37(5), 499-507; DOI: 10.1093/annhyg/37.5.499.
INTRODUCTION:
Pesticides are unusual among occupational chemical hazards, because they are designed to injure or to kill living organisms and are intrinsically toxic. Ideally they would be non-injurious to non-target organisms including man, but most are not highly selective. Therefore, their use should be regulated so that the health and safety of agricultural workers are assured. The key question is: “Are actual exposures safe?” The confidence with which this question can be answered depends on the knowledge of the toxicological properties of the pesticide followed by an assessment of the exposure that may be considered safe. Toxicological evaluation derives the ‘no observed-adverse-effect-levels’ (NOAEL) from experimental studies. The actual exposure must also be known. Comparing this with the NOAEL gives an insight to the risks experienced by the workers. There are several ways to estimate or assess exposure of the field worker. For the levels of exposure many factors are important, including physico-chemical properties of the pesticide, agricultural conditions, working procedure and environmental conditions. The central theme of the present Workshop was to achieve consensus about the optimum approach to:
—measurement of exposure of the agricultural worker, in which both ‘external’ and ‘internal’ exposure, in particular the role of biological monitoring, is considered;
—predictive exposure modelling;
—risk assessment and risk management of occupational exposure to pesticides.
Therefore four papers which follow this review were prepared. During the workshop, which was attended by 28 invited experts (see the List of Participants at the end of this review), the manuscripts were presented and each was critically reviewed by two or three invited respondents. This was followed by in-depth discussions. The present review summarizes the workshop discussions on the different subjects. The various recommendations and proposals that were presented, will be considered as starting points for deriving a harmonized approach to exposure and risk assessment.
Ziska, 2016
Ziska, Lewis H.; “The role of climate change and increasing atmospheric carbon dioxide on weed management: Herbicide efficacy;” Agriculture, Ecosystems & Environment, 2016, 231, 304-309; DOI: 10.1016/j.agee.2016.07.014.
ABSTRACT: Rising concentrations of carbon dioxide [CO2] and a changing climate will almost certainly affect weed biology and demographics with consequences for crop productivity. The extent of such consequences could be minimal if weed management, particularly the widespread and effective use of herbicides, minimizes any future risk; but, such an outcome assumes that [CO2] or climate change will not affect herbicide efficacy per se. Is this a fair assumption? While additional data are greatly desired, there is sufficient information currently available to begin an initial assessment of both the physical and biological constraints likely to occur before, during and following herbicide application. The assessment provided here, while preliminary, reviews a number of physical and biological interactions that are likely, overall, to significantly reduce herbicide efficacy. These interactions can range from climatic extremes that influence spray coverage and field access to direct effects of [CO2] or temperature on plant biochemistry and morphology. Identification of these mechanisms will be essential to both understand and strengthen weed management strategies associated with rising levels of [CO2] in the context of an uncertain and rapidly changing climate.
American College of Obstetricians and Gynecologists, 2014
The American College of Obstetricians and Gynecologists; “Health Disparities in Rural Women;” Committee Opinion, 2014, 586.
ABSTRACT:
Rural women experience poorer health outcomes and have less access to health care than urban women. Many rural areas have limited numbers of health care providers, especially women’s health providers. Rural America is heterogeneous where problems vary depending on the region and state. Health care professionals should be aware of this issue and advocate for reducing health disparities in rural women. FULL TEXT
Diepietro Mager, 2020
DiPietro Mager, Natalie Ann. (2020). Preconception and Interconception Health and Routine Health Service Use Among Women in a Rural Midwestern County (Doctor of Philosophy), Indiana University.
ABSTRACT:
Advancement of preconception and interconception health is a key element to improve women’s health as well as pregnancy outcomes. Little is known about the preconception and interconception health status of rural Midwestern populations in the United States. The primary objective of this study was to determine the preconception and interconception health status as well as behaviors of reproductive age women living in a rural Midwestern area. Secondary objectives were to quantify process measures of health care access and barriers to care, as well as determine disparities in preconception and interconception health status among women in this rural area as compared to statewide estimates. As existing national or state secondary data sources often have limitations in data derived from areas with low population densities or insufficient sample sizes to generate reliable estimates, a cross-sectional study was performed using a 34item survey. Data were collected from February to May 2019 from 315 non-pregnant women ages 18-45 years in a rural county in northwestern Ohio. Nearly all women surveyed had at least one risk factor associated with poor pregnancy outcomes, many of which were modifiable. Nearly half of all respondents reported at least one barrier to receipt of health care services. Women in this rural county fared worse for several preconception and interconception health measures when compared to statewide estimates derived from Behavioral Risk Factor Surveillance System and Ohio Pregnancy Assessment Survey data. These findings illustrate the need for continued development of interventions to improve preconception and interconception health for rural women as well as improved methods to capture and analyze data on important subpopulations at risk.
Bloom et al., 2012
Bloom, T. L., Bullock, L. F., & Parsons, L.; “Rural pregnant women’s stressors and priorities for stress reduction;” Issues in Mental Health Nursing, 2012, 33(12), 813-819; DOI: 10.3109/01612840.2012.712087.
ABSTRACT:
Rural residence and maternal stress are risk factors for adverse maternal-child health outcomes across the globe, but rural women have been largely overlooked in maternal stress research. We recruited low-income, rural pregnant women for qualitative interviews to explore their stress exposures during pregnancy, reactions to stress, and priorities for stress reduction. We also used quantitative measures (Perceived Stress Scale, Center for Epidemiologic Studies of Depression Scale-Revised, Posttraumatic Stress Disorder Checklist-Civilian, Lifetime Exposure to Violence Scale) to describe stress exposures and reactions. We interviewed 24 pregnant rural women from a Midwestern US state, who were primarily young, white, partnered, and unemployed. Women’s predominant stressor was financial stress, compounded by a lack of employment, transportation, and affordable housing options; extended family interdependence; small-town gossip; isolation/loneliness; and boredom. Quantitative measures revealed high levels of global perceived stress, violence exposure, and symptoms of depression and posttraumatic stress disorder among the sample. Women most commonly reported that employment and interventions to increase their employability would most effectively decrease their stress, but faced numerous barriers to education or job training. Tested maternal stress interventions to date include nurse-case management, teaching women stress management techniques, and mind-body interventions. Pregnant women’s own priorities for stress-reduction intervention may differ, depending on the population under study. Our findings suggest that rural clinicians should address maternal stress, violence exposure, and mental health symptoms in prenatal care visits and that clinicians and researchers should include the voices of rural women in the conceptualization, design, implementation, and evaluation of maternal stress-reduction interventions.
Blewett et al., 2004
Blewett, Lynn A., Casey, Michelle M., & Call, Kathleen T.; “Improving Access to Primary Care for a Growing Latino Population: The Role of Safety Net Providers in the Rural Midwest;” Health Services Safety Net, 2004, Summer 2004.
ABSTRACT:
Context: Many rural Midwestern communities are experiencing rapid growth in Latino populations with low rates of health insurance coverage, limited financial resources, language and cultural differences, and special health care needs. Purpose: We report on 2-day site visits conducted in 2001 and 2002 in 3 communities (Marshalltown, Iowa; Great Bend, Kansas; and Norfolk, Nebraska) to document successful strategies to meet Latino health care needs. Methods: We interviewed key informants to identify successful community strategies for dealing with health care access challenges facing the growing Latino population in the Midwest. Findings: Interventions have been developed to meet new demands including (1) use of free clinics, (2) school health programs, (3) outreach by public health, social services and religious organizations, and (4) health care providers’ efforts to communicate with patients in Spanish. Strain on safety net services for Latinos is due in part to a complicated and unstable mix of public and private funds, a large but overtaxed volunteer provider base, the dependence on a limited number of community leaders, and limited time for coordination and documentation of activities. Conclusions: We suggest the development of a Rural Safety Net Support System to provide targeted funding to rural areas with growing immigrant populations. Federal community health center support could be redirected to new and existing safety net providers to support the development of a safety net monitoring system.