What Do Jewelry and E-waste Have In Common?

This week in our environmental epidemiology class one of the main topics of discussion was lead. Our instructor brought up a very interesting source of exposure: lead jewelry. The discussion included a talk about how e-waste is contributing to this problem.

I came across two well-known stories from the United States that demonstrate this issue. In 2003, in Oregon, a 4 year old boy died after swallowing a piece of jewelry bought from a vending machine. Later it was discovered that the toy medallion consisted of 38.8% lead [CDC report, 2004]. More recently, in 2006, another child died from acute lead poisoning in Minnesota, after ingesting a metallic heart-shaped charm. The charm was a gift with purchase from Reebok, which was almost entirely made from lead (99.1%) [CDC report, 2006]. In both instances, the product responsible was imported from abroad. The Consumer Product Safety division of Health Canada, and the Consumer Product Safety Commission in the US, are responsible for ensuring that tragedies like this never happen but evidently things are missed.

Dioxins and Furans: Not in our backyard, yet?

Persistent Organic Pollutants: How did they get there?!

In an earlier post I wrote about polybrominated diphenyl ethers (PBDEs), which are among the list of chemical substances that are classified as persistent organic pollutants (POPs). POPs are chemicals that have three main characteristics: 1) they are stable compounds, enabling them to persist in the environment; 2) they are lipid (fat) soluble, which combined with their stability, enables them to accumulate up the food chain; 3) they have the ability to act as endocrine (hormone) disruptors [1]. New studies continue to discover the presence of POPs in environments where they have never been produced or even used before, indicating their ability to be transported over long-ranges. These characteristics, along with the increasing evidence of adverse health outcomes associated with exposure, have sparked international discussion about the need to urgently reduce and eliminate the production of these chemicals [2].



Dioxins and Furans: Source and Health Impacts

Polychlorinated dibenzo-p-dioxins (PCDDs) and polychlorinated dibenzofurans (PCDFs) are another type of POPs that were studied in the e-waste literature I reviewed. There is a recurrent theme in my postings about the dangers associated with primitive e-waste recycling techniques used in poorer countries where a vast majority of the world's e-waste is processed. In the case of PCDD/Fs, their affiliation with e-waste depends on these crude recycling processes. Plastics made from polyvinyl chloride (26% of the plastic found in e-waste by volume), once processed through uncontrolled open burning, can generate PCDD/Fs [3].



Dioxins and furans can enter the body via inhalation, ingestion and skin absorption. Exposure to PCDD/Fs at high levels can lead to chloracne (severe skin disease), darkening of the skin, and altered liver function. Long-term exposure can lead to damage of the immune, nervous and endocrine systems and impaired reproductive function [3,5]. Specifically, dioxins are classified as Group 1 "known human carcinogens" according to the World Health Organization's (WHO) International Agency for Research on Cancer [4]. These carcinogenic effects have only been observed with high dose exposures; there is insufficient evidence to prove that low-level exposure to dioxins and furans can cause cancer [5].



The Tolerable Monthly Intake for dioxins and furans is 70 picograms per kilogram of body weight (pg/kg), as outlined by the WHO. This is the amount that can be ingested per month over a lifetime without inducing substantial health risk [5].



What's been reported in the E-waste literature?

A number of studies have quantified the level of PCDD/Fs in air, soil, dust, sediment, freshwater, fish, and cow milk samples, in a number of regions where e-waste recycling has taken place [6]. My interests lied in those studies that quantified human internal exposure to these hazardous agents, using biological markers such as human breast milk, placenta, hair, blood and urine. I did review one study that estimated daily human exposure using many environmental samples (soil, dust, and surface samples). This study was an interesting starting point for my research in this area because I kept these estimates in mind when looking at the studies that measured internal exposure using biological markers. The estimated daily intake of PCDD/Fs via soil/dust ingestion and dermal exposure, according to this study, was two times higher for people who are exposed to e-waste recycling facilities in Taizhou (2.3 and 0.363 pg/kg/day for children and adults, respectively), compared to people who are exposed to chemical industrial sites (0.021 and 0.0053 pg/kg/day for children and adults, respectively) in various areas also in Eastern China [7]. Note that these estimates did not include a number of other sources of PCDD/Fs exposure such as through food, water, breast milk etc.



From here I turned to another study that was a health risk assessment (systematic calculation of risk) of dioxins and furans, using samples of human milk, placenta and hair from residents also in the Taizhou region*. The 10 study participants were all women of child-bearing age who had been either exposed to e-waste recycling activities as residents in Taizhou, or unexposed residents in a neighbouring city (245 km away from Taizhou) for at least two years, and who had given birth at either of two study sites between August and December 2005. Each biological sample provided a different picture of the overall exposure. PCDD/Fs in hair samples indicated accumulation and atmospheric deposition on the hair surface; consequently, it is difficult to distinguish between internal and external contamination [8]. Analysis of the placenta is a good indication of prenatal exposure, and breast milk samples reflects maternal body burden and the postnatal transfer of PCDD/Fs to infants [9].



The results showed that there were significantly different PCDD/F concentrations in the placenta and hair samples after comparing the exposed group to the unexposed group. The total concentrations found in breast milk samples from the exposed group were two times higher than the unexposed group, but this difference was not found to be statistically significant (p>0.05). Background pollution, dietary habits and personal characteristics were all important factors influencing the total concentrations of PCDD/Fs [9]. All human milk samples from the Taizhou group, and 80% of the samples taken from the women in the reference group, exceeded the European Union's maximum permitted levels in milk (3 pg WHO-TEQ/g lipid) [10]. The health risk assessment for infants estimated that the daily intake of PCDD/Fs via breast milk was 102.98 +/- 67.65 pg TEQ/kg body weight/day in the exposed group and 45.83 +/- 36.22 pg TEQ/kg body weight/day in the unexposed. Both of these values exceed the WHO tolerable daily intake (1-4 pg TEQ/kg body weight/day) [11]. High intake exceeding the toxicological limit during breast feeding is concerning because of the long length of time that it takes for the toxins to be removed from the body (7 to 12 years), faster and greater absorption in infants and children, and the immature body defenses in infants [9].



A third study was found that measured PCDD/F concentrations in hair samples from 64 randomly selected male workers at e-waste factories in eastern China. The study did not have it's own comparison group, and was therefore not looked at in great detail. The results from this study similarly found vastly greater concentrations of PCDD/Fs in hair samples analyzed compared to other known contaminated areas, and compared to the concentrations found in healthy study participants in Japan [12].



Tying things together

At the beginning of this post I mentioned that one of the properties of POPs is that they can travel over long distances. I was kind of surprised to have never really found a comprehensive article reviewing whose health is being affected by e-waste (big and small, currently or in the future). I read a bunch of media articles and blog posts talking about how as North Americans, we don't really experience the major effects of the international shipment and mismanagement of e-waste. I think this is a huge misconception, because we are all impacted by e-waste, even if we aren't the ones working in the family-owned workshops. If not in the present, then most likely in the future, we will all be impacted by e-waste if innovative and stricter policies aren't implemented.



Hopefully this is motivation for those decision makers that aren't motivated by the devastating results presented above, and in previous posts, about the human health impacts already occurring.





* Taizhou has become one of the main receivers of e-waste in China, in recent years. It receives an estimated 2.2 million tonnes of e-waste on an annual basis, and the industry employs an estimated forty thousand people. Most of the recycling that takes place in this region involves open burning, acid baths, and manual disassembly of e-waste [9].

What Are You Leaving Behind?

When you move on to the latest technology, what happens to the items you leave behind? 
Well, it gets added to the 4,750 tonnes of lead, 4.5 tonnes of cadmium, and 1.1 tonnes of mercury contained in personal electronics that are disposed in Canada each year, according to Environment Canada [1].  These figures are grossly underestimated.  

Slightly more than half of the metals that are found in a typical desktop computer include copper, aluminum, lead, gold, zinc, nickel, tin, silver, and iron, while the remaining portion is composed of platinum, palladium, mercury, cobalt, antimony, arsenic, barium, beryllium, cadmium, chromium, selenium and gallium [2]. One of the reasons we don't want old electronics to end up in landfills is because toxic metals such lead and mercury can leach into the water and soil, and eventually circulate throughout the food chain, and possibly end up in our bodies [2]. While equipment is intact, these heavy metals don't pose a risk to human health, but when electronics are discarded and/or recycled in uncontrolled environments, the hazardous components are released into the environment posing great amounts of risk [2,3]. Despite the fact that most heavy metals are toxic and bioaccumulative at low concentrations, the main heavy metals investigated in the e-waste disposal literature that I found were lead, beryllium, cadmium and mercury.

Health Risks of Lead Exposure
Lead is one of the most commonly used heavy metals -- it is used in both computer and television screens, and in the solder used to anchor various circuit board components. Toxicity tests of laptops, VCRs, printers and remote-control devices have been conducted in the US, and found that a substantial proportion of these electronics exceeded the US safety standards for lead [3].  The main reason for having a product safety standard for lead is because its deleterious effects on human health have been widely studied, and are well known to be quite serious.  According to Health Canada, short term exposure to high levels of lead can cause vomiting, diarrhea, convulsions, coma or even death. The main areas of the body affected by lead are the brain, kidney, and nervous system [4]. Once exposed to lead, it can remain in your body for years in bone or circulating through the blood stream [5]. Children are particularly susceptible to lead at even lower levels of exposure, due to increased absorption. The harms noted in children include impacts on intellectual development, behaviour, size and hearing. During pregnancy, lead can also cross the placenta and affect the unborn child. Studies have shown that female workers who are exposed to high levels of lead have more miscarriages and stillbirths [4,5].  In Canada, corrective action is taken when patients present with blood lead levels exceeding 10 micrograms per decilitre [4]. Recent studies have shown that blood lead levels lower than 10 micrograms per decilitre were associated with reduced IQ scores and academic skills [6]; therefore, no level of exposure has been deemed safe.

Health Risks of Beryllium Exposure    
Beryllium is sometimes used in circuit boards as an electrical connector and/or to insulate microprocessors [2].  When improperly handled during disposal or recycling, beryllium dust can be released, which is known to cause severe lung disease and lung cancer [6,7]. Exposure thresholds have not been accurately set for beryllium in Canada, according to a recent risk assessment for generic e-waste processing facilities in Canada [8]. Interestingly, this Canadian risk assessment found exposure levels to both lead and beryllium to be above the occupational exposure limits outlined by the ACGIH. The current occupational exposure limit in Ontario is 0.002 micrograms per meter cubed (time–weighted average exposure value) [9].  

Health Risks of Cadmium Exposure
The predominant use of cadmium is in rechargeable batteries. In addition to this, cadmium can be found in plastics, cadmium plated steel, solders, and TV picture tubes [10]. Cadmium toxicity can lead to kidney, bone, and pulmonary damage. There are three modes of exposure: dermal, pulmonary (lungs), and gastrointestinal (mouth); cadmium cannot cross the placenta. The main organ for long-term cadmium accumulation is the kidney, hence its toxic effects on the kidney with life-time exposure [11]. Acute toxicity due to cadmium exposure can lead to nausea, vomiting, weakness, shortness of breath, lung edema (fluid in the lungs) and possibly death [11,12].  Chronic exposure has been linked to kidney damage, bone mineral density loss and hypertension [13]. Additionally, the International Agency for Research on Cancer classifies cadmium as carcinogenic, with exposure primarily linked to lung cancer [14]. Currently, there is no Canadian blood cadmium guidance value for the general population; although, according to the preliminary results from the new Canadian Health Measures Survey, the geometric mean blood cadmium in Canadians aged 6 to 79 was 0.35 micrograms per litre [13]. 

Health Risks of Mercury Exposure
An estimated 22 percent of the mercury used world-wide each year goes into electrical and electronic equipment, including batteries, flat-panel display screens, and switches [15]. Even though very small amounts of mercury are used in these products, very small levels of mercury exposure are known to cause damage to the brain, spinal cord, kidneys, liver and a developing fetus. The human health risks of mercury exposure have been recognized for quite some time, and consequently is a well researched area.  To date, mercury exposure is understood to have neurological, renal (kidney), cardiovascular and immunological impacts.  In extreme cases, long-term exposure can lead to coma or death. Neurodevelopmental problems in children can also develop as a result of mercury exposure while in the womb [16,17].  Recent studies have noted adverse health events occurring at even lower mercury exposure levels [16].  The Health Canada guidance value for total blood mercury concentrations is 20 micrograms per litre for adults (a threshold value has not been set for children) [17].

Flame Retardants: Here, There... Everywhere

"We're definitely eating them and probably inhaling a small amount" said Dr. Arnold Schecter, professor of environmental sciences at the University of Texas Health Centre[1].

What Dr. Schecter is referring to are the unseen but widely found polybrominated diphenyl ethers (PBDEs) that are almost guaranteed to be present in any home or area where high-tech electronics like TVs, computers or cell phones have been in use [1,2]. PBDEs are synthetic chemical compounds that are used as flame retardants (chemicals that are added to polymers to prevent fires) in upholstery furniture, carpet backing textiles, foam, plastics, and electrical and electronic equipment [1,2]. Great concern has been expressed by a number of researchers about the escalating volume of PBDEs that are persistent in the environment, and their potential to disrupt endocrine function, neurodevelopment and increase ones risk of cancer [3,4]. It was incredible learning about the various environmental media that PBDEs have been detected in: air, water, sediment, soil and biota from literally across the globe [1,3,4,5]. PBDEs have been detected in human adipose tissue, blood, and breast milk, and repeat measures have proven that these concentrations are clearly increasing over time [1,2,5].

PBDE Exposure and E-Waste

In my literature search I came across two studies that looked at both human internal exposure to PBDEs associated with e-waste disassembly, and two health outcomes thought to be related to exposure: increased cancer incidence and altered thyroid function. Both studies conclude with a plea for more research on the human health impacts of exposure to PBDEs, since there is an apparent gap in the present scientific literature. A number of in vitro and in vivo studies have been conducted, however, few studies have involved humans.

In the study that looked at cancer and PBDE exposure, the researchers assessed the level of internal exposure to PBDEs among a convenience sample of cancer patients living around an e-waste disassembly site [6]. After an increasing incidence of cancer (such as liver and lung cancer) was noted among residents surrounding the e-waste disassembly site, the researchers decided to look at the body burden of PBDEs (through kidney, lung and liver tissue samples) among local cancer patients who visited a surgical ward. Unfortunately, the study did not have a comparison group; therefore the association between cancer and PBDE exposure in e-waste dumping grounds could not be measured. The study could only conclude that the PBDE internal exposure levels for the study participants (174.1-182.3 ng/g lipid) were notably higher than those reported among the European population, but comparable to those reported in the USA population (based on previous exposure studies). The study also identified the main congeners of PBDEs in the tissue samples (PBDE47, PBDE28 and PBDE209), which was consistent with previous measures of food, air particles, e-waste residues and soil samples collected from the disassembly site in an earlier study. These findings suggest that the congeners can enter the body through three main routes of exposure: inhalation, ingestion and skin penetration. Clearly, a more in-depth investigation of the potential association between cancer and PBDE exposure is needed. After a quick literature search of PBDEs and cancer on MEDLINE I could only find one case control study of non-Hodgkin lymphoma published in 1998 [7].

The second study I looked at was a cross-sectional study of residents in two villages: a village close to an e-waste recycling site (exposed group) and a village located 50 km away from the e-waste site (control group) [8]. Due to PBDEs’ structural similarity to thyroid hormone and polychlorinated biphenyls (PCBs), researchers have been investigating their ability to cause thyroid hormone disruption and DNA damage (can lead to cancers and developmental disorders) [8,9,10] . In the following study, the researchers measured serum levels of PBDEs as an indicator of internal exposure, serum levels of thyroid stimulating hormone (TSH) as an indicator of thyroid function (host response), as well as urinary 8-hydroxydeoxyguanosine (8-OHdG) and frequencies of the cytokinesis-block micronucleus (CBMN) as indicators of the presence of DNA damage. Not only was the median concentration of total PBDEs in the atmosphere of the e-waste recycling site 47 times higher than the concentration in the control site (7149 vs. 150 pg/m³, respectively), but also the median serum PBDEs level for the exposed participants was more than twice that in the controls (382 vs. 158 ng/g lipid, respectively). These median serum levels in both villages were notably higher than those previously reported from studies in Spain (median, 12 ng/g lipid)[11], New Zealand (median, 7.17 ng/g lipid) [12], and Japan (median, 2.89 ng/g lipid) [13].

The results also showed that the levels of serum TSH among the participants exposed to e-wastes were significantly increased (p<0.01). A dose response trend was noted between the levels of PBDE exposure and TSH levels; however, the study did not account for other pollutants within the e-waste dismantling site that may have impacted thyroid hormone homeostasis. The study did account for some factors that can affect the balance of TSH in the human body (ie. BMI, age and sex), however, a number of endogenous and exogenous factors were not measured, reducing the strength of these findings.

With respect to DNA damage, there was no evidence of excess oxidative DNA damage (8-OHdG) that may have been caused by PBDE exposure. The researchers suspect that this may have been because the study was underpowered. The CBMN assay did however find that having a history of working with e-wastes increased ones risk for micronucleated binucleated cells (MNed BNC) 28-fold. Current evidence suggests that these MNed BNC can lead to cancer (14,15). Although two in vitro studies were cited as connecting PBDEs to an increased frequency of MNed BNC, exposure to other genotoxic agents found in e-waste but not included in the study, must be accounted for in future studies.

The study findings do suggest that PBDE exposure may indeed interfere with the thyroid hormone system and cause genetic damage, but further studies are needed. The alarmingly high level of exposure in both villages in Zhenjiang emphasizes the need for enhanced surveillance and control of the occupational and environmental exposure to PBDEs, particularly in areas where e-waste recycling is taking place. Even though human health effects of PBDEs exposure are only starting to be increasingly explored, a number of countries and organizations are recommending the mitigation of environmental exposure. The US Environment Protection Agency has already classified decaBDEs (one of three mixtures of PBDEs) as possible human carcinogens [16], and two PBDE congeners have already been banned in the European Union since 2004 [17].

What is Canada doing?

- As of December 2006, Environment Canada and Health Canada have prepared screening assessments on several PBDEs.

o Health Canada’s screening assessment found human PBDE exposure estimates to be well below the levels believed to cause health effects in laboratory animals.

- The Government of Canada now prohibits the production, use and importation of specific PBDEs.

- Health Canada has implemented ongoing food monitoring and will continue to conduct research on PBDEs [2].

Do What You Can.Ca

I've been looking for a site that directs people to reputable e-recycling companies in Ontario. I'm really excited because I just found one. The site is called dowhatyoucan.ca and it's great because you can search by type of waste, postal code or community. It lists only those collection sites that are certified by the Ontario Electronic Stewardship (OES), the industry funded organization that ensures that goods are handled in a secure and environmentally sound manner. This may seem strange that I'm recommending a site that is funded by the industry, but the OES works in cooperation with the Ministry of the Environment and Waste Diversion Ontario to uphold the Waste Diversion Act introduced in 2002. Allow me to explain further.

If you've ever recycled old electronics in the past you probably remember how expensive it was to do so. It can be a real deterrent for most people when they're asked to pay up to 30% of the original cost of the electronic device. This April, 2009, a really exciting program was launched in Ontario: Phase 1 of the Waste Electrical and Electronic Equipment (WEEE) Program plan. This program now allows you to take your old devices and drop them off at the designated locations (see dowhatyoucan.ca) for FREE!

There has been a gradual shift of responsibility onto brand owners to ensure the proper disposal of their products [1]. Brand owners, first importers, franchisers, and assemblers currently need to pay fees that go towards the WEEE Program. The OES, which proposed and operates the WEEE program, has already received approval for Phases 1 and 2 of the program from the Minister of the Environment [2]. The main difference between the two phases lies in the list of products that are accepted for disposal. If you click this link you can review a list of the products that qualify under Phases 1 and 2. You'll notice that Phase 1 only includes a small proportion of WEEE products. The program is being implemented in stages to allow for adequate collection and recycling infrastructure to develop. Also this will allow the OES to evaluate the program performance prior to launching Phase 2 [3]. At first I was disappointed by this protracted implementation plan, but I actually think it makes a lot of sense. At the very least I'm hoping this allowance for infrastructure development has avoided or reduced the temptation to ship e-waste overseas due to overwhelming amounts. Recycling depots would be inundated with e-waste if all of the electronics destined for landfills were diverted to them. Overseas shipment of e-waste would be an even more tempting solution, especially if industry was paying for their products to "disappear".

Personally, I would still ask the collection agent where the items are recycled to ensure that the products are indeed being recycled locally. I recommend asking the collection agents for details first and if they don't know I would contact the Electronics Product Stewardship Canada or the Ontario Electronic Stewardship.

When E-waste Becomes A Security Issue

According to the 2009 Converge IT Asset Disposition (ITAD) Trends Report, "almost twice as many American IT managers said data security is more important to their organizations than being green when it comes to IT asset disposal." Although the report notes that there is better awareness of e-waste policies and procedures, I found their motivation for proper e-waste disposal to be quite interesting.

To elaborate on the security issue, there has been increasing concerns about the mishandling of personal information left on old electronics. In the introductory film previously posted, e-waste is presented as an explanation for why Ghana is the world's leading country for cyber crime. Ghana, being one of the known international e-waste dumping grounds, has been identified as a central region where electronic recyclers extract personal information such as credit card and bank account numbers to commit fraudulent acts.

At the end of the day it seems that IT managers could ensure both better security and greener disposal by utilizing local, reputable disposal companies. As long as both ends are achieved, I guess this is progress??