Potential health risks due to in-car aerosol exposure across ten global cities

Car microenvironments significantly contribute to the daily pollution exposure of commuters, yet health and socioeconomic studies focused on in-car exposure are rare. This study aims to assess the relationship between air pollution levels and socioeconomic indicators (fuel prices, city-specific GDP, road density, the value of statistical life (VSL), health burden and economic losses resulting from exposure to fine particulate matter ≤2.5 µm; PM_2.5) during car journeys in ten cities: Dhaka (Bangladesh); Chennai (India); Guangzhou (China); Medellín (Colombia); São Paulo (Brazil); Cairo (Egypt); Sulaymaniyah (Iraq); Addis Ababa (Ethiopia); Blantyre (Malawi); and Dar-es-Salaam (Tanzania). Data collected by portable laser particle counters were used to develop a proxy of car-user exposure profiles. Hotspots on all city routes displayed higher PM_2.5 concentrations and disproportionately high inhaled doses. For instance, the time spent at the hotspots in Guangzhou and Addis Ababa was 26% and 28% of total trip time, but corresponded to 54% and 56%, respectively, of the total PM_2.5 inhaled dose. With the exception of Guangzhou, all the cities showed a decrease in per cent length of hotspots with an increase in GDP and VSL. Exposure levels were independent of fuel prices in most cities. The largest health burden related to in-car PM_2.5 exposure was estimated for Dar-es-Salam (81.6 ± 39.3 μg m^-3), Blantyre (82.9 ± 44.0) and Dhaka (62.3 ± 32.0) with deaths per 100,000 of the car commuting population per year of 2.46 (2.28-2.63), 1.11 (0.97-1.26) and 1.10 (1.05-1.15), respectively. However, the modest health burden of 0.07 (0.06-0.08), 0.10 (0.09-0.12) and 0.02 (0.02-0.03) deaths per 100,000 of the car commuting population per year were estimated for Medellin (23 ± 13.7 μg m^-3), São Paulo (25.6 ± 11.7) and Sulaymaniyah (22.4 ± 15.0), respectively. Lower GDP was found to be associated with higher economic losses due to health burdens caused by air pollution in most cities, indicating a socioeconomic discrepancy. This assessment of health and socioeconomic parameters associated with in-car PM_2.5 exposure highlights the importance of implementing plausible solutions to make a positive impact on peoples' lives in these cities.

Maternal pesticide exposure and child neuro-development among smallholder tomato farmers in the southern corridor of Tanzania

BACKGROUND

Exposure to pesticides with its associated effects prenatally and in early childhood has not received much attention. There is little scientific data on this aspect in Tanzania therefore this study was meant to contribute to the deficit in the subject.

METHOD

A cross-sectional study was conducted to a sample of 286 participants of mother to child pair, whereby 172 and 114 were exposed and non-exposed respectively. Mothers who had been working in tomato sprayed farms were exposed and mothers who had not been working in the tomato sprayed farms were un-exposed. Child aged 0-6 years was chosen from each mother sampled but only one child found to be the youngest with the classified age was enrolled. Malawi child development Tool (M-DAT) was employed to assess the child level of development, height, and weight of the children were collected and analyzed by the WHO anthropometric calculator. A checklist and questionnaire were used to observe and assess maternal exposure. Bivariate and Multivariate analysis were conducted to assess the relationship between various factors of exposure.

RESULTS

Overall 15% of the children examined were not well developed and the most used pesticides were those posing neuro-development effects. On the bivariate analysis model, mothers who worked while pregnant were more likely to have a child with neuro-developmental effect OR=5.8(1.29-26.3). On multivariate analyses adjusted for age of the mother, variables which remain in the model were a distance from home [AOR=9.4(4.2-20.5)], and working while pregnancy [AOR=5.8(1.29-26.3)] other were removed due to collinearity effect. None of confounders had a potential significant effect but only nutrition seems to be the effect modifier [AOR=7.8(1.29-36.3)] when analyzed with working while pregnancy.

CONCLUSIONS

The findings from this study have indicated that maternal pesticide exposure among farmworker residents in the SAGCOT area has a potential association with child developmental effect.

In-car particulate matter exposure across ten global cities

Cars are a commuting lifeline worldwide, despite contributing significantly to air pollution. This is the first global assessment on air pollution exposure in cars across ten cities: Dhaka (Bangladesh); Chennai (India); Guangzhou (China); Medellín (Colombia); São Paulo (Brazil); Cairo (Egypt); Sulaymaniyah (Iraq); Addis Ababa (Ethiopia); Blantyre (Malawi); and Dar-es-Salaam (Tanzania). Portable laser particle counters were used to develop a proxy of car-user exposure profiles and analyse the factors affecting particulate matter ≤2.5 μm (PM_2.5; fine fraction) and ≤10 μm (PM_2.5-10; coarse fraction). Measurements were carried out during morning, off- and evening-peak hours under windows-open and windows-closed (fan-on and recirculation) conditions on predefined routes. For all cities, PM_2.5 and PM₁₀ concentrations were highest during windows-open, followed by fan-on and recirculation. Compared with recirculation, PM_2.5 and PM₁₀ were higher by up to 589% (Blantyre) and 1020% (São Paulo), during windows-open and higher by up to 385% (São Paulo) and 390% (São Paulo) during fan-on, respectively. Coarse particles dominated the PM fraction during windows-open while fine particles dominated during fan-on and recirculation, indicating filter effectiveness in removing coarse particles and a need for filters that limit the ingress of fine particles. Spatial variation analysis during windows-open showed that pollution hotspots make up to a third of the total route-length. PM_2.5 exposure for windows-open during off-peak hours was 91% and 40% less than morning and evening peak hours, respectively. Across cities, determinants of relatively high personal exposure doses included lower car speeds, temporally longer journeys, and higher in-car concentrations. It was also concluded that car-users in the least affluent cities experienced disproportionately higher in-car PM_2.5 exposures. Cities were classified into three groups according to low, intermediate and high levels of PM exposure to car commuters, allowing to draw similarities and highlight best practices.

Pesticide Use and Serum Acetylcholinesterase Levels among Flower Farm Workers in Ethiopia-A Cross-Sectional Study

The flower industry in East Africa has grown in recent years, especially in the production and export of roses. The aim of this study was to assess pesticide use on selected flower farms in Ethiopia. Serum cholinesterase levels in workers were used as a marker of pesticide exposure. This study was a cross-sectional study involving 588 workers from 15 different flower farms. It had a response rate of 95.5%. The participants included 277 males (mean age 26 years; 148 pesticide sprayers and 129 non-sprayers) and 311 females (mean age 25 years; 156 working in greenhouses and 155 working outside the greenhouses). The researchers undertook structured interviews, blood sampling, and walkthrough surveys. Descriptive statistics and Poisson regression were used in the statistical analyses. A total of 154 different trade names of pesticides were found. Of them, 31 (27%) were classified as moderately hazardous by the WHO, and 9% were organophosphates. Serum levels of cholinesterase deviating from 50-140 Michel units were considered abnormal. Abnormal serum cholinesterase levels (above 140 Michel units) were found in 97 participants (16.5%, 95% confidence interval 13.7-19.7%). There were no differences between the four job groups regarding cholinesterase levels. The high prevalence of abnormal serum cholinesterase levels might indicate the presence of pesticide intoxication. Thus, there is a need for routine monitoring of all workers exposed to pesticides, not only sprayers.

Health Symptoms Associated with Pesticides Exposure among Flower and Onion Pesticide Applicators in Arusha Region

INTRODUCTION

Pesticides are extensively used in agriculture to control harmful pests and prevent crop yield losses or product damage. In Tanzania several studies have been conducted on health effects of pesticides on agricultural workers. However, there are few studies on neurological health symptoms associated with pesticide exposure in flower and onion farms.

OBJECTIVE

The objective of this cross-sectional study was to assess health symptoms associated with pesticide exposure among flower and onion pesticide applicators in the Arusha region, Tanzania.

METHODS

Data on demographic variables and health symptoms associated with pesticide exposure were collected from 140 males who were employed in spraying pesticides on flower and onion farms in Arusha, Meru and Karatu districts between April and May 2017. The study participants were interviewed using a structured questionnaire with questions focusing sociodemographic characteristics, occupation, pesticide exposure, common type of pesticide used in the area and neurological symptoms experienced during and after pesticide spraying. To determine the intensity of pesticide exposure, acetylcholinesterase assay was done by using the Test-mate Model 400 device with a photometric sensor.

RESULTS

Ninety-five percent of pesticide applicators reported handling organophosphate pesticides. Body weakness was the most frequently reported neurological symptom (57.1%) followed by perspiration and headache (40.7%), poor appetite and depression (29.3%) and irritation (26.4%). About 27% of pesticide applicators had an acetylcholinesterase level below the limit value.

CONCLUSION

A high proportion of neurological health symptoms and cholinesterase test depression was noted among pesticide applicators in both farms. There is a need to conduct further studies to ascertain causality for such high instances of neurological symptoms.

Pesticide Exposure and Health Problems Among Female Horticulture Workers in Tanzania

Commercialization of horticulture farming, expansion of farms, and the practice of monoculture favor the proliferation of pests, which in turn increases the need for pesticides. Increased exposure to pesticides is associated with inadequate knowledge on the hazardous nature of pesticides, poor hygiene practices, lack of availability of washing facilities, and insufficient adherence to precautionary instructions on pesticide labels. Mitigating the risks posed by pesticides is considered a less compelling interest than alleviating poverty. Women working in horticulture in Tanzania usually have low levels of education and income and lack decision-making power even on matters relating to their own health. This contributes to pesticide exposure and other health challenges. Because of multiple factors, some of which act as study confounders, few studies on exposure to pesticides and health effects have been conducted among women. This review identified factors that contribute to the increased health effects among women working in the horticultural industry and how these effects relate to pesticide exposure.

Assessment of the ability of health care providers to treat and prevent adverse health effects of pesticides in agricultural areas of Tanzania

A survey of Tanzanian health care providers in agricultural areas was undertaken in 1991-1994 to assess their knowledge of toxic effects of pesticides, experiences and practices, as well as of their needs for appropriate information in order to develop effective strategies for reducing pesticide poisoning. Face-to-face interviews were conducted with 104 physicians, clinical officers and nurses at health care facilities in the coffee and cotton growing areas. Eighty percent of respondents reported to have seen one and nine of them two to four cases of pesticide poisoning in the preceding three months. A significantly higher annual number of poisonings were observed in coffee than in cotton area (GM 0.5 vs 0.1). Also the number of cases registered in hospitals was considerably higher than that in the out-patient health care (GM 1.7 vs 0.2). Pesticide poisoning was regarded as a major problem in the community by 63% of health care providers, including 77% of hospital staff. One third of health care providers thought that a certain percent of pesticide poisoning cases remain unrecognized, and that this percentage is higher in cotton than in coffee growing areas. The respiratory tract was the major route for pesticide to enter the human body; this was followed by gastrointestinal tract, skin, and eyes. Only one percent of the respondents could identify the groups of pesticides (organophosphate vs organochlorine) mostly used in the study areas. The survey indicated that training of hospital staff in toxicity of pesticide exposure is an important task and a prerequisite for efficient recognition, diagnosis and treatment of pesticide poisoning cases in Tanzania.

Pesticide-handling practices in agriculture in Tanzania: observational data from 27 coffee and cotton farms

The practices of pesticide handling in agriculture were surveyed in 1991-1993 in Tanzania, to identify hazardous practices and farms where they occurred. The study involved 23 coffee farms with 246 persons exposed to hazardous practices, and four cotton farms with 45 exposed. An observation form addressed locations of important places with respect to pesticide spraying, storage, disposal, and equipment; personal protection; and hygiene. More pesticide formulations were used for coffee compared with cotton and by individual rather than cooperative farms. Coffee farms more often had unlabeled pesticide containers and missing mixing instructions, while cotton pesticides were stored in bedrooms, near food, and near open fires, and pesticide leftovers were often present. Hazardous practices were more pronounced at individual than cooperative farms, with significant differences in pesticide storage areas, as well as unlabeled and non-original containers. The study demonstrated the need to train farmers in pesticide safety, strengthen advisory and regulatory services, and extend protection to farm workers' families.

Acute health effects of organophosphorus pesticides on Tanzanian small-scale coffee growers

Acute health effects of organophosphorus (OP) pesticides on coffee farmworkers in 1991-1992 in Tanzania are reported to provide a basis for concern over farmworkers being overexposed during application. Workers exposed to OP pesticides (N=133) were drawn from a population of about 240,000 coffee farmers. They were interviewed on symptoms and personal protection, and their erythrocyte acetylcholinesterase (AChE) activity was determined during both spraying and nonspraying period. AChE activities during spraying and nonspraying period were comparable (mean 32.0, SD 7.8 vs. 33.0, SD 8.7 U/g HgB, P=0.26). The prevalence of cough, headache, abdominal pain, excessive sweating, nausea, excessive salivation, diarrhea, and vomiting did not differ significantly between spraying and nonspraying periods. There was no suggestion of decreased AChE in exposed subjects who complained of OP-related symptoms compared to symptomless exposed subjects. Use of gloves, long boots, head cover, face cover, and coverall was not significantly associated with AChE activity. No marked AChE depression was found during spraying season, which may explain the lack of association between symptoms and AChE. The fact that only moderately toxic OP pesticides were used may indicate that toxicity was not sufficiently high to cause depression. Experience, however, suggests that occupational poisoning remains a potential serious danger in coffee cultivation in Tanzania.

Collaboration between developing and developed countries and between developing countries in occupational health research and surveillance

Collaborative occupational health and safety studies between counterparts in developing and developed countries and between developing countries have demonstrated their potential for improving occupational health and safety. Such collaboration in occupational health and safety is encouraged in the development of infrastructure in research empowerment and capacity building. This action includes the setting of priorities, the identification and documentation of problems, sponsorship, data bases and surveillance systems, technical support, methodology, publishing, research and training programs, controlled intervention, information exchange, and networking. Examples of priorities in occupational health and safety in the developing world include the informal sector (informally hired and independent workers), temporary work, pesticides, accidents, dusts, carcinogens, solvents, ergonomics, women and child labor, human immunodeficiency virus/acquired immunodeficiencey syndrome (HIV/AIDS), and transfer of hazardous materials and technologies. The sustainability of occupational health and safety structures and functions in the developing countries is a primary concern. Socioethical principles emphasize local, national, mutual and global gains. Examples of collaboration are given. Pervasive problems and strategies toward their solution are highlighted.