Nisha Naicker

Retrospective Investigation of a Lead Poisoning Outbreak from the Consumption of an Ayurvedic Medicine: Durban, South Africa.

Ayurvedic medicines have been gaining in popularity around the world in recent decades, but have also been associated with lead contamination and poisoning. In 2012 in Durban, South Africa, a lead poisoning outbreak among adolescents was associated with the consumption of an Ayurvedic medicine for the treatment of skin conditions. In 2014 eight individuals (out of 12 affected) were traced and interviewed. Questionnaires were administered; blood samples were taken for lead content analysis; and medical records were reviewed. Samples of the implicated medicines were analyzed to determine lead levels. Blood lead levels during the acute phase ranged from 34 to 116 µg/dL; and during the current study (two years later) from 13 to 34 µg/dL. The implicated lead capsules had a lead content of 125,235 µg/g. Participants suffered a wide range of non-specific ill health symptoms; and there was a significant delay in the diagnosis of lead poisoning. This study highlights the potential for lead poisoning outbreaks from the consumption of Ayurvedic medicines in African settings. There were weaknesses with regard to the diagnosis of and response to the outbreak, for which measures need to be put in place to ensure greater awareness of the role of Ayurvedic medicine in lead poisoning, and prompt diagnosis and treatment of future cases.

Environmental lead--a public health challenge in South Africa.

© 2013 Lippincott Williams & Wilkins www.epidem.com | 621 To the Editor: Blood lead levels in developing countries are generally higher than international guideline levels due to the unabated use of lead in formal and informal industries.1 this is especially worrisome in countries such as south Africa, where there are limited public resources to regulate exposure and mitigate adverse effects. In 2002, a cross-sectional survey had assessed lead exposure in elementary-age children in three south African cities (Kimberley, Cape town, and Johannesburg), documenting high levels of lead exposure. In 2007, we conducted a follow-up study in elementary-age children attending the same schools in the same cities. Finger-prick blood tests were conducted using the LeadCare 1 analyser system (esA Biosciences Inc, Chelmsford, MA). Although this was not the method used in the 2002 survey, this system has been shown to be reliable and with similar results to more formal analytic methods.2,3 the Us Centers for Disease Control and Prevention has recently recommended a reference level of 5 μg/ dL, based on the Us population of children aged 1–5 years. We used this level to dichotomize blood leads.1 A total of 1349 elementary-age students (51% boys and 49% girls) participated in the survey. the mean age was 7.6 years, with ages ranging from 5 to 12 years. twelve percent were from the smaller city of Kimberley, 36% from Cape town, and 52% from Johannesburg. the majority of households were impoverished, with 33% earning less than r1000 (UsD 125) per month. Mean blood lead in the total sample was 8.0 μg/ dL, with a median of 7 μg/dL. Individual blood lead levels ranged from 0.8 to 32.3 μg/dL; 74% of the sample had blood lead levels at 5 μg/dL or higher, and 25% had levels above 10 μg/dL. In Johannesburg, 84% of children had blood lead levels of 5 μg/dL or higher, whereas the proportions were 57% in Kimberley and 66% in Cape town (table). In the 2002 survey, 35% of children in the same schools in Johannesburg had had blood lead levels of >10 μg/dL compared with 33% in 2007. this minimal reduction in exposure may reflect the discontinuation of leaded gasoline. similar decreases have been found in other countries.4–7 However, there was an apparent increase in blood lead levels in Cape town and Kimberley. In 2002, only 10% of children in the same schools had had blood lead levels in excess of 10 μg/dL, compared with 18% and 13%, respectively, in 2007.8 In just 5 years, an additional 8% of children in Cape town and an additional 3% of children in Kimberley were classified in the most heavily lead-exposed category. this suggests there are pockets of children in urban south Africa who continue to experience substantial lead exposure, despite the removal of major lead sources. It must be noted that different methods were used to assess blood lead levels in the two surveys; however, previous studies have found results from LeadCare to be comparable to formal laboratory analytical methods.3 We find that 1 to 2 years after discontinuation of leaded gasoline, children’s blood lead levels in urban south Africa remain high, and in some areas are increasing. the disabilities related to childhood lead exposure are well documented and preventable. More attention to this public health problem is urgently needed.

Exposure to lead in South African shooting ranges

Introduction: Lead exposure in shooting ranges has been under scrutiny for decades, but no information in this regard is available in respect of African settings, and in South Africa specifically. The aim of this study was to determine the blood lead levels in the users of randomly selected private shooting ranges in South Africas Gauteng province. Methods: An analytical cross sectional study was conducted, with participants recruited from four randomly selected shooting ranges and three archery ranges as a comparator group. Results: A total of 118 (87 shooters and 31 archers) were included in the analysis. Shooters had significantly higher blood lead levels (BLL) compared to archers with 36/85 (42.4%) of shooters versus 2/34 (5.9%) of archers found to have a BLL ≥10 &mgr;g/dl (p<0.001). Conclusion: Shooting ranges may constitute an import site of elevated exposure to lead. Improved ventilation, low levels of awareness of lead hazards, poor housekeeping, and inadequate personal hygiene facilities and practices at South African shooting ranges need urgent attention. HighlightsThis is the first study, to our knowledge, of lead exposure in shooting ranges in an African setting.This study indicates highly elevated lead exposure amongst the users of certain private shooting ranges in South Africa.Lead exposure may be a serious, yet under‐studied, source of adult lead exposure in South Africa, and possibly elsewhere on the African continent.

The association between environmental lead exposure with aggressive behavior, and dimensionality of direct and indirect aggression during mid-adolescence: Birth to Twenty Plus cohort

Chronic lead exposure is associated with neurological ill-health including anti-social behavior such as aggressive behavior. The main aim of this study was to examine the association between lead exposure at 13years old and dimensions of aggressive behavior during mid-adolescence. The study sample included 508 males and 578 females in mid-adolescence (age 14 to 15years) from the Birth to Twenty Plus cohort in Johannesburg, South Africa. Blood samples collected at age 13years were used to measure blood lead levels. Seventeen items characterizing aggression from the Youth Self Report questionnaire were used to examine aggressive behavior. Principal Component Analysis was used to derive composite variables from the original data for aggressive behavior; and data were examined for an association between blood lead levels and dimensionality of direct and indirect aggression and disobedience during mid-adolescence. We also examined the dimensions of aggression during mid-adolescence in relation to gender and socio-demographic factors. Blood lead levels ranged from 1 to 28.1μg/dL. Seventy two percent of males and 47.7% of females in the study had blood lead levels ≥5μg/dL. There was a positive association between elevated blood lead levels and direct aggression (p<0.05). Being male was positively associated with direct aggression (p<0.001) but, negatively associated with indirect aggression (p<0.001). Maternal education and age at birth were negatively associated with direct aggression during mid-adolescence. The significant association between elevated blood lead levels and direct aggressive behavior observed in this study may shed light on a possible environmental toxicological contribution to aggressive behavior in South African youth; and most importantly the type of aggressive behavior associated to lead exposure.

Indoor Temperatures in Low Cost Housing in Johannesburg, South Africa

Ambient and indoor temperature affects thermal comfort and human health. In a changing climate with a predicted change in temperature extremes, understanding indoor temperatures, both hot and cold, of different housing types is important. This study aimed to assess the hourly, daily and monthly variation in indoor temperatures in different housing types, namely formal houses, informal houses, flats, government-built low-cost houses and old, apartheid era low-cost housing, in five impoverished urban communities in Johannesburg, South Africa. During the cross-sectional survey of the Health, Environment and Development study data loggers were installed in 100 homes (20 per suburb) from February to May 2014. Indoor temperature and relative humidity were recorded on an hourly basis. Ambient outdoor temperatures were obtained from the nearest weather station. Indoor and outdoor temperature and relative humidity levels were compared; and an inter-comparison between the different housing types were also made. Apparent temperature was calculated to assess indoor thermal comfort. Data from 59 retrieved loggers showed a significant difference in monthly mean indoor temperature between the five different housing types (p < 0.0001). Low cost government-built houses and informal settlement houses had the greatest variation in temperature and experienced temperatures between 4 and 5 °C warmer than outdoor temperatures. Housing types occupied by poor communities experienced indoor temperature fluctuations often greater than that observed for ambient temperatures. Families living in government-built low-cost and informally-constructed homes are the most at risk for indoor temperature extremes. These types of housing should be prioritised for interventions aimed at assisting families to cope with extreme temperatures, gaining optimal thermal comfort and preventing temperature-related health effects.

The association between elevated blood lead levels and violent behavior during late adolescence: The South African Birth to Twenty Plus cohort

Epidemiological studies have shown the adverse neuro-behavioral health effects of lead exposure among children, in particular. However, there is lack evidence in this regard from developing countries. The main aim of this study was to assess the association between blood lead levels (BLLs) during early adolescence and violent behavior in late adolescence. Our study sample from the Birth to Twenty Plus cohort in Soweto-Johannesburg, South Africa included 1332 study participants (684 females). BLLs were measured using blood samples collected at age 13years. Violent behavior was evaluated using data collected at ages 15 to 16years using the Youth Self Report questionnaire. First, bivariate analysis was used to examine data for an association between lead exposure in early adolescence and violent behavior items during late adolescence. Principal Component Analysis (PCA) was used for dimensionality reduction and six violent behavior components were derived. Data were further analyzed for an association between BLLs at age 13years and violent behavior using PCA derived components; to determine the specific type(s) of violent behavior associated with lead exposure. Median whole BLLs were 5.6μg/dL (p<0.001). Seventy five percent of males and 50% of females had BLLs≥5μg/dL. BLLs ranging from 5 to 9.99μg/dL were associated with physical violence (p=0.03) and BLLs≥10μg/dL were associated physical violence and fighting (p=0.02 and p=0.01, respectively). When data were analyzed using continuous BLLs physical violence was associated with lead exposure (p<0.0001). Furthermore, males were more likely to be involved in violence using a weapon (p=0.01), physical violence (p<0.0001), and robbing others (p<0.05) compared to females. The results from this study show the severe nature of violent behavior in late adolescence associated with childhood lead exposure. They highlight the urgent need for preventive measures against lead exposure among children in low or middle income countries such as South Africa.

Environmental lead exposure and pubertal trajectory classes in South African adolescent males and females

The effects of environmental lead exposure in the neuro-endocrine system have been shown to impact the maturation and tempo of puberty development in adolescents. In low and middle income countries very little is known regarding the detrimental health effects of childhood lead exposure with regard to the tempo of puberty development. To help address this gap in data, we examined the association between lead exposure and puberty progression in males and females. Study participants from the urban Birth to Twenty Plus (BT20+) birth cohort in Soweto-Johannesburg, South Africa with data for blood lead levels at age 13years, cord blood lead levels, pubic hair development and breast development in females, and pubic hair development and genital development in males, were included in this study. The sample comprised 1416 study participants (n=684 females). Pubertal development trajectory classes were defined using Latent Class Growth Analysis. Data were examined for (i) an association between cord blood lead levels and pubertal trajectory classes; and (ii) an association between blood lead levels at age 13years and pubertal trajectory classes. In females, there was an association between adolescent elevated blood lead levels (≥5μg/dL) and lower level of maturation at age 9years and slower progression of pubic hair and breast development (relative risk ratio (RRR)=0.45, p<0.0001; 95% CI (0.29-0.68)) and (RRR=0.46, p<0.01; 95% CI (0.27-0.77)), respectively. In males, elevated blood lead levels at birth were associated with slower tempo of pubic hair development (RRR=0.20, p<0.05). Findings from this study suggest a possible role for environmental lead in altering pubertal development in South African adolescents as shown by slower tempo of progression through the Tanner stages pubertal development in females and males. There were also gender-differences between the effects of prenatal and postnatal lead exposure during pubertal development.

Is There a Relationship between Lead Exposure and Aggressive Behavior in Shooters

Lead exposure has been associated with psycho-neurological disorders. Elevated blood lead levels have been found in shooters. This study assesses the association between the blood lead levels of shooters and their levels of aggression. An analytical cross-sectional study was conducted in Gauteng, South Africa. Participants were recruited from four randomly selected shooting ranges with three randomly selected archery ranges used as a comparison group. A total of 118 (87 shooters and 31 archers) participants were included in the analysis. Aggressiveness was measured using the Buss-Perry Aggression Questionnaire. Shooters had significantly higher blood lead levels (BLL) compared to archers with 79.8% of shooters versus 22.6% of archers found to have a BLL ≥ 5 μg/dL (p < 0.001). Aggression scores were significantly higher in shooters (p < 0.05) except for verbal aggression. In the bivariate and regression analyses, shooters with BLLs ≥ 10 μg/dL were significantly associated with the hostility sub-scale (p = 0.03, adjusted odds ratio (OR) 2.83, 95% confidence interval (CI) 1.103–7.261). Shooters have a significantly higher BLL and aggressiveness compared to archers. However, elevated blood lead levels were significantly associated with hostility only. Interventions need to be put in place to prevent continued exposure and routine screening of populations at risk should be implemented.

Concentrations of arsenic and lead in residential garden soil from four Johannesburg neighborhoods

ABSTRACT The 2017 Lancet Commission on Pollution and Health identified soil as an important, daily route of public exposure to a variety of pollutants. Lead and arsenic are two potential soil contaminants associated with serious health effects including reductions in intelligence, behavioral effects and aggressive or violent behavior (lead), as well as skin changes, cancer of the skin, bladder, liver and lungs and developmental delays (arsenic). In this study soil samples were collected, using US EPA methods, from gardens in four Johannesburg neighborhoods, and analyzed for lead and arsenic content using a portable X‐ray fluorescence spectrometer. The results showed widely varied concentrations of arsenic and lead in soil collected across the four neighborhoods. Concentrations of lead (range: 0.1–2141.0 mg/kg; mean: 241.7 mg/kg (SD 282.8); median 158.1 mg/kg) exceeding local and international reference levels were found in an inner city suburb, while raised arsenic concentrations (range: 0.1–65.3 mg/kg; mean: 18.3 mg/kg (SD 11.7); median: 19.1) were found in the gardens of a suburb located very close to a mine tailings facility. This study confirms the potential for high levels of exposure to toxic metals in residential gardens in an urban African setting. There is a pressing need for scaled up attention to the public health implications of exposure to soil pollution in developing countries.

Gender invariance of the Self-Reporting Questionnaire (SRQ-20)

The World Health Organization 20-item Self-Reporting Questionnaire is a quick, low-cost screening instrument for measuring common mental disorders and has been applied in community-based health surveys in developing countries. It was originally designed as a general single factor tool for assessing mental distress associated with several common mental disorders. However, studies have also examined alternate multi-factor solutions for the Self-Reporting Questionnaire–20 across diverse study populations. A cross-sectional household survey was conducted in August and September 2009 among adults living in five urban communities in Johannesburg, South Africa (n = 360). The Self-Reporting Questionnaire–20 was used to assess common mental disorders in the past month. Confirmatory factor analysis was applied to compare three competing models (one-, two-, and three-factor models). All three models fit the data well. Gender invariance was tested on the one-factor model based on its extensive application in clinical and research settings. Our findings did not support gender invariance. The differences in factor loadings between male and female subgroups suggest that the application of the Self-Reporting Questionnaire–20 may be more suited to women and therefore should be used cautiously for the assessment of common mental disorders in South Africa urban populations.