Recycling of scrap metal into artisanal cookware in the informal sector: A public health threat from multi metal exposure in South Africa

Cottage industry as a source of high exposure to lead: A biomonitoring study among people involved in manufacturing cookware from scrap metal

In low-income countries, a widespread but poorly studied type of cottage industry consists of melting scrap metal for making cookware. We assessed the exposure to lead (Pb) among artisanal workers, and their families, involved in manufacturing cookware from scrap metal. In a cross-sectional survey, we compared artisanal cookware manufacturing foundries with carpentry workshops (negative controls) and car battery repair workshops (positive controls), all located in residential areas, in Lubumbashi (DR Congo). We collected surface dust in the workspaces, and blood and urine samples among workers, as well as residents living in the cookware workshops. Trace elements were quantified in the samples by Inductively Coupled Plasma Mass Spectrometry (ICP-MS). In surface dust, median Pb concentrations were higher in cookware foundries (347 mg/kg) than in carpentries (234 mg/kg) but lower than in battery repair workshops (22,000 mg/kg). In workers making the cookware (n = 24), geometric mean (GM) Pb blood cencentration was 118 μg/L [interquartile range (IQR) 78.4-204], i.e. nearly twice as high as among carpenters [60.2 μg/L (44.4-84.7), n = 33], and half the concentration of battery repair workers [255 μg/L (197-362), n = 23]. Resident children from the cookware foundries, had higher urinary Pb [6.2 μg/g creatinine (2.3-19.3), n = 6] than adults [2.3 (2.2-2.5), n = 3]. Our investigation confirms the high Pb hazard linked to car battery repair and reveals a high exposure to Pb among artisanal cookware manufacturers and their families, especially children, in residential areas of a city in a low-income country.

Evaluating metal cookware as a source of lead exposure

BACKGROUND

We previously demonstrated that aluminum cookware brought from Afghanistan by resettled families as well as some aluminum cookware available for purchase in the United States represent a previously unrecognized source of lead exposure. However, the extent to which this cookware represents a source of lead exposure to other United States residents is unclear.

OBJECTIVES

To test additional cookware for lead content and its propensity to leach lead and other toxic metals. This will further our understanding of the extent to which this cookware represents a lead poisoning risk in the United States and elsewhere.

METHODS

We screened an additional 28 pieces of aluminum cookware and 5 brass items for lead content using an X-ray fluorescence (XRF) analyzer and used our leachate method to estimate the amount of lead that migrates into food. We also tested 17 additional stainless steel items to determine whether they would be safer alternatives.

RESULTS

Many aluminum cookware products contained in excess of 100 parts per million (ppm) of lead. Many also leached enough lead under simulated cooking and storage conditions to exceed recommended dietary limits. One hindalium appam pan (an Indian frying pan/wok) leached sufficient lead to exceed the childhood limit by 1400-fold. Brass cookpots from India also yielded high lead levels, with one exceeding the childhood limit by over 1200-fold. In contrast, stainless steel cookware leached much lower levels of lead.

IMPACT

Aluminum and brass cookware available for purchase in the United States represents a previously unrecognized source of lead exposure.

Metal exposures from source materials for artisanal aluminum cookware

Artisanal aluminum cookware releases lead and other metals that pose significant health risk for people in low and middle-income countries. Cookware is made from recycled engine and electronic appliance parts, cans, and other materials. We obtained fourteen custom-made pots from Ghana, produced from seven different scrap aluminum sources. We sought to determine whether avoiding certain source materials could reduce leaching of metals. Cooking was simulated using dilute acetic acid and palm oil. Aluminum released from all pots exceeded recommended guidelines. Variable amounts of lead, cadmium, chromium, nickel and other metals were leached, with the most lead coming from auto radiators and mixed metals. Pots made from engine blocks did not yield detectable amounts of lead. All pots released potentially harmful concentrations of two or more metals. Selective scrap aluminum sourcing for recycled cookware does not avoid metal contamination of food, although some sources may release lower concentrations of certain metals.

Investigating aluminum cookpots as a source of lead exposure in Afghan refugee children resettled in the United States

BACKGROUND

Afghan refugee children resettled in Washington State have the highest prevalence of elevated blood lead levels (BLLs) of any other refugee or immigrant population. Resettled families brought several lead-containing items with them from Afghanistan, including aluminum cookpots.

OBJECTIVES

To evaluate the potential contribution of lead-containing cookpots to elevated BLLs in Afghan children and determine whether safer alternative cookware is available.

METHODS

We screened 40 aluminum cookpots for lead content using an X-ray fluorescence (XRF) analyzer and used a leachate method to estimate the amount of lead that migrates into food. We also tested five stainless steel cookpots to determine whether they would be safer alternatives.

RESULTS

Many aluminum cookpots contained lead in excess of 100 parts per million (ppm), with a highest detected concentration of 66,374 ppm. Many also leached sufficient lead under simulated cooking and storage conditions to exceed recommended dietary limits. One pressure cooker leached sufficient lead to exceed the childhood limit by 650-fold. In contrast, stainless steel cookpots leached much lower levels of lead.

SIGNIFICANCE

Aluminum cookpots used by refugee families are likely associated with elevated BLLs in local Afghan children. However, this investigation revealed that other U.S. residents, including adults and children, are also at risk of poisoning by lead and other toxic metals from some imported aluminum cookpots.

IMPACT STATEMENT

Some aluminum cookware brought from Afghanistan by resettled families as well as cookpots available for purchase in the United States represent a previously unrecognized source of lead exposure.

Ergonomic Risk Assessment during an Informal Hand-Made Cookware Operation: Extending an Existing Model

The work conducted in the informal sector is highly variable within and between days. Characterizing ergonomic exposures remains a challenge because of unstructured work settings and schedules. The existing ergonomic risk assessment tools have been widely used in formal work settings with a narrow range of exposure, and for predefined tasks that primarily constitute a daily routine. There is limited information in the literature on how they have been applied in informal workplaces. The aim of this study was to extend an existing risk assessment tool and to evaluate the applicability of the extended tool by assessing ergonomic exposure related to hand-made cookware operations. Eighteen hand-made cookware makers were recruited from six sites. A walkthrough risk assessment questionnaire was used to collect information on workers, tasks, work stations and workplace structures. The Rapid Upper Limb Assessment (RULA) screening tool was extended by including duration and vibration. An action priority matrix was used to guide intervention. According to the RULA action levels, the workers required investigation and changes soon, and immediate investigation and changes. The use of an action priority matrix was appropriate, and indicated that all the workers assessed were within the high to very high exposure domain and required immediate corrective measures. The methodology used proved to be an effective and reliable strategy for identifying ergonomic exposure among hand-made cookware makers.

Lead Poisoning among Male Juveniles Due to Illegal Mining: A Case Series from South Africa

Illegal mining is a major public health and societal concern. Recent scientific evidence indicates elevated blood–lead levels in illegal gold miners and associated communities. Yet, there is little research in this regard from low- to middle-income countries (LMICs), where illegal mining is growing. This case series is extracted from a cross-sectional study of lead exposure in incarcerated juveniles in greater Johannesburg. From survey records (blood–lead levels and questionnaires), three males had elevated blood–lead levels and presented with health conditions and behavioural problems putatively linked with lead poisoning. Based on the record review, all three juveniles were in a secure facility due to illegal mining-related activities. All three cases had high blood–lead levels and demonstrated a tendency toward aggressive or violent behaviour. They also presented with conditions associated with lead poisoning, such as anaemia, respiratory illness, abdominal disorders, and musculoskeletal conditions. Juveniles involved in illegal mining are at risk of exposure to heavy metals such as lead, and there is a need for relevant preventative action and health care programmes in this group.

Exposure to lead and other toxic metals from informal foundries producing cookware from scrap metal

Metal exposure remains a significant public health problem, particularly in the informal sector. The rise in informal foundries to cast scrap metal into artisanal cookware is widespread in low- and middle-income countries. The main aim of this study was to characterize metal exposure in artisanal cookware makers working in informal foundries in South Africa by measuring lead (Pb) in blood as well as sample metal concentrations on hands before and after work. The blood Pb distribution of the artisanal pot makers ranged from 1.1 to 4.6 μg/dl with the median blood Pb level being 2.1 μg/dl (IQR 1.7-2.5). The median blood Pb level in artisanal pot makers was 1.0 μg/dl higher compared with the non-exposed community members (p < 0.0001). Before-and-after handwipe sampling revealed a median increase in all 22 elements. Pre and post aluminum (Al) load on the handwipes revealed a 7.3 factor increase (0.53 and 3.9 mg Al/handwipe respectively) (p = 0.003). Hand Pb load before and after pot making revealed a 3.5-fold increase (median increase of 6.2 μg Pb/handwipe). An increase in backyard informal foundries may be linked to increased exposure to toxic metals for workers, family members and communities.

Release behavior of metals from tin-lined copper cookware into food simulants during cooking and cold storage

The copper pots with an inner coating layer of tin have been remarkably used in many countries for a long time. In this study, leaching of some metals from tin-lined copper pots into food simulators at different pHs (4, 5.5, 7, and 8.5) during boiling processing (95 °C for 1, 2, and 3 h) or refrigerated storage (4 °C for 1, 2, and 3 days) was investigated. Citric acid and sodium hydroxide were used to adjust the pH of food simulators. The leaching concentrations of metals were analyzed by inductively coupled plasma optical emission spectrometers (ICP-OES). Scanning electron microscopy (SEM) was used to indicate the surface morphological properties of cookware. Based on the preliminary experiments, metals including Al, Sn, Cu, Mn, Fe, Ca, Na, Cr, Mg, and Zn were selected to analyze in acidic treatments. Furthermore, Al, Cu, Sn, Na, and Ca were analyzed for neutral and alkaline ones. Results showed that the boiling temperature for 3 h resulted in a much higher migration of metals compared with cold storage for 3 days. Mn and Cr showed the lowest metal concentration during cooking and cold storage, respectively. The concentration of Sn in acidic simulators was remarkably higher than the other metals during both cooking and refrigerated storage. However, Ca during cold storage, as well as Na during both cooking and cold storage, showed the most migration in alkaline solutions, among the other pHs. An acidic simulator with pH 4 showed the most considerable release of metals from copper pots. SEM results indicated more intense surface corrosion by acidic solution (pH 4) than alkaline one. In general, longer cooking and cold storage durations led to increasing metals release. The migration of the studied metals demonstrates the impurities of the tin layer of these cookwares that may lead to acute and/or chronic diseases.

Occupational Exposure to Fine Particulate Matter (PM4 and PM2.5) during Hand-Made Cookware Operation: Personal, Indoor and Outdoor Levels

(1) Exposure of informal artisanal cookware makers to fine particles has not yet been characterized. The aim of this study was to characterize occupational exposure to fine particulate matter (PM4 and PM2.5) levels and fine particulate matter (PM2.5) elemental components; (2) Artisanal cookware makers were recruited from five cookware making sites. Exposure to fine particulate matter was measured for 17 male participants. SidePak personal aerosol monitors (AM520) were used to measure personal exposure to PM4, while a DustTrak monitor and an E-sampler were used to assess indoor and outdoor PM2.5 levels, respectively. A questionnaire was administered to capture information on demographic characteristics. The chemical characterization of indoor and outdoor PM2.5 filter mass was conducted using Wavelength Dispersive X-ray Fluorescence. Time series record of 15-min averages for indoor and outdoor PM2.5 levels were assessed; (3) The median (range) was 124 µg/m3 (23-100,000), 64 µg/m3 (1-6097) and 12 µg/m3 (4-1178), respectively, for personal PM4, indoor and outdoor PM2.5. The highest levels for many of the elemental components of PM2.5 were found in the outdoor PM2.5 filter mass and (4). The information generated during this study may assist in extending occupational health and safety strategies to artisanal cookware makers and developing targeted prevention initiatives.

Recycled aluminium cooking pots: a growing public health concern in poorly resourced countries

Lead exposure remains a significant public health problem, particularly in the informal sector. Recycling of scrap metal into artisanal pots is a growing concern in poorly resourced countries. Owing to the relatively light weight and low cost of the artisanal pots, as well as good conductivity which equates to lower usage of wood fuel, the pots are widely used. The aim of this article is to describe current insights and emerging evidence of health risks associated with artisanal pot making and usage. This thriving industry, particularly in poorly resourced communities, has multifaceted occupational, environmental and human health impacts. Given the complexity, innovative solutions need to be prioritized, evaluated and scaled up in relevant settings.