3.1 Health impacts from an airbag system
An airbag is a cushion that inflates rapidly in the case of a car accident in order to protect the driver of the car and passengers from death and severe injuries. The inflation of the airbag is controlled by an electronic control unit, which together with the airbag constitutes the airbag system. The company Autoliv is a producer of safety devices for cars, including airbag systems, and had explored environmental impacts of their products in a number of ELCA studies (Iwanek and Samiee
2010; Mujiyanto and Priyojati
2010; Suyang and Jingjing
2010; Munnwer et al.
2012). The company then expressed an interest in investigating social impacts along the life cycle of their airbag system as well. It was decided that the aim of the study should be to compare the injuries and lives lost during the product life cycle of an airbag system with the injuries prevented and lives saved during its use (Baumann et al.
2013). The driver airbag consists of six components (label, nut, cushion, can, cover and inflator) and the electronic control unit consists of five components (label, cover, housing, screw and printed circuit board), which in turn both consist of different materials, such as metals and petrochemicals (Mujiyanto and Priyojati
2010; Suyang and Jingjing
2010). All these components, including their supply chains, were considered in the study, and the functional unit was one frontal airbag system. However, waste treatment of the airbag system was not included in the study.
The social indicator employed to fulfil the aim of the study was DALY, as described in Sect. 2.1. DALY was chosen since it can be used to quantify both impacts that an airbag system aims at avoiding during its use phase and health impacts from the rest of the airbag system’s life cycle. Parts of the airbag system’s production system were deemed to probably not have notable health impacts, while four areas were deemed in need of scrutiny: (1) emissions of toxic substances along the life cycle, (2) work environment impacts during mining of metals, (3) work environment impacts during electricity generation, and (4) work environment impacts during production of pyrotechnical material for the inflator.
Toxic emissions and pyrotechnical materials are obvious health hazards. Metals account for a large part of the airbag system by weight, and mining activities cause higher health impacts than many other industries (Coleman and Kerkering
2007). Electricity generation is also known to be an industry with considerable casualties, particularly for some energy sources (Wilson et al.
1999). The use phase of the airbag system was also assessed in terms of DALY avoided. The equation used to calculate the net DALY of the airbag system in this case study was thus:
$$ {\mathrm{DALY}}_{\mathrm{airbag}\ \mathrm{system}}={\mathrm{DALY}}_{\mathrm{toxic}}+{\mathrm{DALY}}_{\mathrm{mining}}+{\mathrm{DALY}}_{\mathrm{electricity}}+{\mathrm{DALY}}_{\mathrm{pyrotechnical}}+{\mathrm{DALY}}_{\mathrm{use}\ \mathrm{phase}} $$
(4)
Data on metal amounts, electricity use and toxic emissions were obtained from previously conducted ELCA studies of Autoliv’s airbag and electronic control unit (Mujiyanto and Priyojati
2010; Suyang and Jingjing
2010). The ReCiPe impact assessment method was applied for assessing the DALY from toxic emissions along the life cycle of the airbag system (Goedkoop et al.
2013). Only health impacts due to human toxicity were included. Furthermore, the ReCiPe method includes three different value perspectives that represent different views on environmental issues. The individualist perspective is based on short-term interests and technological optimism. The hierarchist perspective is based on the most common policy principles regarding time frame and other assumptions and is recommended as a default. The egalitarian perspective is more precautionary and takes a long-term perspective. In the assessment of the airbag system, the hierarchist perspective was employed.
Data on number of lives lost from mining of metals were obtained from accident statistics in an Australian mining fatalities database (Department of Mines and Petroleum
2010). Data on casualties per kilowatt-hour for different kinds of electricity generation were obtained from two published sources (Wilson et al.
1999; Starfelt and Wikdahl
2011). Some of this electricity casualty data were global averages, some were specific for different countries (such as China and the USA), and some for regions (such as Europe). The data obtained on accidents and casualties in mining and electricity generation were calculated into DALY by application of the average global life expectancy (World Health Organization
2011) as well as durations and severity factors for relevant injuries (Polinder et al.
2007).
The pyrotechnical materials used by Autoliv are produced in-house, and we obtained information about their production from the producer. According to this information, there were no fatal or serious injuries recorded for many years. Thus, after this investigation, the production of pyrotechnical materials was deemed to have a negligible contribution to the net DALY.
The DALY avoided in the use phase were obtained based on annual lives saved and injuries prevented by Autoliv’s seatbelts and airbag systems. By application of the attribution method described by Glassbrenner (
2003), the lives saved and injuries prevented were divided between seatbelts and airbag systems. This attribution method is called restraint-neutral attribution, which does not give any preference to either of the two safety products. In order to convert to functional unit, lives saved and injuries prevented were divided by the annual number of sold airbag systems by Autoliv. Again, assumptions about life expectancy, injury duration, and injury severity factor had to be made.
The results of the study showed that the DALY caused during the product life cycle of the airbag system were considerably lower than the DALY avoided from its use in traffic. The DALY caused were approximately 8 × 10−5 years per airbag system, whereas the DALY avoided were approximately 1 × 10−2 years. The largest contribution to DALY caused was accidents during electricity generation and toxic emissions during the whole life cycle, which contributed by approximately equal shares. Since the DALY avoided were more than 100 times higher than the DALY caused, the result indicates that the purpose of an airbag system, which is to save lives and prevent injuries, seems to be justified.
The sensitivity analysis showed that the results were robust. However, Autoliv does not perform the waste treatment themself, and the end of life process for airbag systems is thus uncertain. Incineration of electronic waste may cause emissions of hazardous substances. In order to test the importance of the omission of waste treatment, the amount of emissions to air from incineration of the electronic control unit that would result in the DALY caused exceeding the DALY avoided was calculated. This was done for three typical electronic waste incineration contaminants, namely dioxins, lead and polycyclic aromatic hydrocarbons (PAH) (Swedish Environmental Protection
2011). For dioxins, emissions of about 10 mg per airbag system during waste treatment would result in the DALY caused exceeding the DALY avoided. For lead and PAH, the corresponding numbers were much higher. The main recommendation to Autoliv was therefore to try to avoid emissions of dioxins at the milligram level or higher during waste treatment through life cycle management initiatives.
3.2 Health impacts from a catalytic converter
Catalytic converters convert the toxic exhaust gas emissions of carbon monoxide (CO), uncombusted hydrocarbons (HC) and nitrogen oxides (NO
x) into the non-toxic gases water (H
2O), carbon dioxide (CO
2) and nitrogen (N
2). As a follow-up study to the assessment of the airbag system, we wanted to know if a catalytic converter used to reduce exhaust gases in cars avoids more DALY than it causes (Islam
2015). Amatayakul and Ramnäs (
2001) had already shown that a catalytic converter caused more environmental impact throughout its life cycle than it avoided in the use phase. Their results showed that environmental impacts from mining of platinum group metals (PGM) in South Africa outweighed the environmental gains from the converter’s use phase. The question was whether a catalytic converter also causes more health impacts throughout its life cycle than it avoids in the use phase, and whether the PGM mining would once again turn out to dominate the impact.
A catalytic converter consists of six main components: ceramic honeycomb (19 % of weight), insulating material (2 %), wash coat (4 %), PGM catalyst (<1 %), steel housing (68 %), and heat shield (7 %). The production of these was included in the study, along with the use phase of the converter in a passenger car. Different recycling rates were also tested in the study.
The health impacts included were expanded compared to the airbag system study. Instead of merely considering emissions contributing to human toxicity, also emissions contributing to global warming, ozone depletion, photochemical smog, ionizing radiation and particulate matter were considered. These are all impact categories that contribute to human health impacts according to the ReCiPe method (Goedkoop et al.
2013). DALY avoided in the catalytic converter’s use phase were similarly quantified by assessing avoided health impacts from the reduced emissions with the ReCiPe method.
Work environment impacts for all processes were included this time, and not only for mining and electricity generation as in the airbag system study. Scanlon et al. (
2015) had developed characterization factors for work environment impacts for a large number of industrial activities. These include both injuries (such as bruises, wounds and traumatic injuries) and workplace exposure to chemicals. They are calculated as the ratio between the work environment-related DALY for a specific industry and the amount of physical output from that industry:
$$ C{F}_{\mathrm{WE},n}=\frac{{\mathrm{DALY}}_n}{m_n} $$
(5)
where
CF
WE,n
is the work environment characterization factor for the industry
n and
m
n
is the physical output of the industry
n. An example of an industry
n is iron ore mining, and the DALY
n
then quantifies the annual years of disability caused in the iron ore mining industry. The output
m
n
is given as kilograms of iron ore in that case, and the
CF
WE,n
then takes the unit of years of disability per kilograms iron ore. The characterization factors by Scanlon et al. (
2015) apply for working conditions in the USA, but they were doubled for South Africa, Russia and other countries outside Europe in order to account for presumed higher work environment impacts.
The net DALY of the catalytic converter was calculated as:
$$ {\mathrm{DALY}}_{\mathrm{catalytic}\ \mathrm{converter}}={\mathrm{DALY}}_{\mathrm{emissions}}+{\mathrm{DALY}}_{\mathrm{workplace}\ \mathrm{accidents}}+{\mathrm{DALY}}_{\mathrm{use}\ \mathrm{phase}} $$
(6)
Overall, the net DALY varied between approximately −5 and 7 days, meaning that the converter could cause more health impacts than are avoided. Impacts from emissions to the environment—affecting the general population—turned out to be considerably larger than health impacts in the workplace environment. The results showed that whether a catalytic converter avoids more DALY than it causes depends mainly on the time perspective in the ReCiPe method. For the individualist and hierarchist perspectives, which consider time frames up to 100 years, the catalytic converter is a net provider of health regardless of other assumptions. For the egalitarian perspective, for which an infinite time frame is considered, the catalytic converter is generally a net depriver of health. However, increased recycling rate and functional lifetime of the converter could make it a net provider of health also for the egalitarian perspective. Regardless of value perspective and other assumptions, the main contributor to DALY caused was indeed the PGM mining (ca 80 %).
3.3 Health impacts from gold jewellery
Gold was suggested as a potentially interesting product to study from a health perspective in the article by Baumann et al. (
2013), mainly due to two reasons: The use of mercury in small-scale gold mining, and the role of gold in conflicts. In this case study, human health impacts of gold jewellery production were assessed in order to investigate whether the mercury and conflicts, or other processes, resulted in high health impacts (Parsmo
2015). Gold jewellery was chosen over other uses of gold in order to avoid difficult-to-assess avoided health impacts in the use phase. For example, gold is used in electronic medical instruments, which could have positive health impacts. Such assessments would require data on the health impacts of such instruments and allocation of those impacts to the gold components. Gold production in the Democratic Republic of the Congo (DRC), South Africa and Sweden was considered. Besides the gold production system, the production of mercury was also included in the DRC case.
Health impacts from emissions, including those of mercury, were assessed with the ReCiPe method. Similarly to the catalytic converter study, all six impact categories contributing to human health were included (human toxicity, global warming, ozone depletion, photochemical smog, ionizing radiation and particulate matter). Work environment impacts were also assessed in the same way as in the catalytic converter study, using the characterization factors provided by Scanlon et al. (
2015). The influence of increasing the value of these characterization factors to account for more severe working conditions was investigated in the sensitivity analysis. Violence related to robbery during the retailing and use phases of gold jewellery was not included due to lack of data, although jewellers’ shops are typical targets of armed robberies that sometimes result in injuries (O’Donnell and Morrison
1997).
What makes this study different from the other two, apart from that there is no avoided DALY in the use phase, is the influence of the product to the continuation of a conflict. The conflict that the gold contributes to is (mainly) the Second Congo War and its aftermath in the DRC. This conflict started in 1998 when President Laurent Kabila ordered Rwandan military to leave the country. Although the war was first fought mainly between the newly installed government of Kabila and foreign powers such as Rwanda, Uganda and Burundi, additional military groups soon joined the fighting. The conflict has been described as the bloodiest since World War II, and 5.4 million people are estimated to have lost their lives as a result of the conflict (Coghlan et al.
2007). This death toll not only is partly due to combat actions but also includes casualties due to diseases such as AIDS and severe contagion among refugees with limited access to food and clean water.
The role of gold and other minerals in the conflict is not trivial to assess. The long-lasting conflict in the DRC arguably has various other causes, including ethnic tension, poor economy, colonial power and its withdrawal, conflict over land, absence of security and non-functional governmental institutions (Thom
1999; Ndikumana and Emizet
2003; Turner
2007). However, there are several reasons to believe that the conflict may not have taken place were it not for the presence of minerals in the region or at least would not have been as bloody and long lasting. First, there are witness observations of overtaking of mines by various military groups, promises of gold to people joining military forces and direct killings of people to get access to areas rich in minerals (Human Rights
2005; Global
2009; Amnesty
2013). Second, economic analyses show that the revenue from minerals serves as an economic basis for providing weapons. An evaluation of eight conflicts in the DRC between 1960 and 2000 concluded that seven out of eight conflicts were partly our fully financed by natural resources (Ndikumana and Emizet
2003). The revenues can come directly from the minerals or from enforcing road taxes on transporting minerals. Third, many neighbouring countries, most notably Rwanda, Burundi and Uganda, have an economic interest in the mineral extraction, and people living in these countries are benefiting economically from the trade (Ndikumana and Emizet
2003; Mullins and Rothe
2008). For example, Uganda produced 500 US dollars worth of gold in 2007 but exported 27 million US dollars worth of gold the same year (Granatstein and Young
2009). The difference between these two numbers is likely unofficial imports from the DRC. Fourth, an economic study evaluating parameter increasing the probability of civil war concluded that the geographical concentration of natural resources significantly increased the probability of civil war in regions, especially during the 1990s (Ndikumana and Emizet
2003). Although other factors certainly play an important role in the conflict, it was assumed in the gold jewellery study that the minerals are accountable for all deaths in the conflict.
The conflict-related DALY caused by the gold was estimated in a similar manner as work environment health impacts were assessed by Scanlon et al. (
2015) (Eq.
5). The number of DALY caused by the gold was calculated by dividing the DALY caused in the conflict with the gold production from 1998 to 2006 and allocated to gold by economic value:
$$ {\mathrm{DALY}}_{\mathrm{conflict},\mathrm{A}\mathrm{u}}=a\times \frac{{\mathrm{DALY}}_{\mathrm{conflict},\mathrm{total}}}{m_{\mathrm{Au}}} $$
(7)
where
a is an allocation factor and
m
Au is the mass of gold (Au) produced in the DRC between 1998 and 2006. The allocation by economic value is conducted between gold, tin, tantalum, cobalt, diamonds and copper, since these are the economically most important minerals in the region. The allocation factor
a is thus a ratio between the economic value of the produced gold between 1998 and 2006, and the total economic value of all included minerals during the same time period. This allocation gives gold a share of approximately 7 % of the conflict casualties.
The net DALY of the gold jewellery was calculated as:
$$ {\mathrm{DALY}}_{\mathrm{gold}\ \mathrm{jewellery}}={\mathrm{DALY}}_{\mathrm{emissions}}+{\mathrm{DALY}}_{\mathrm{workplace}\ \mathrm{accidents}}+{\mathrm{DALY}}_{\mathrm{conflict}} $$
(8)
The baseline result for the DRC shows that the DALY per gold ring (containing 4 g of gold) is approximately 0.4 years, and the DALY per kilogram gold is approximately 100 years. The main contributors are, as suspected, the conflict (ca 99 %) and emissions of mercury (ca 1 %). Other contributions were minor. For gold production in South Africa and Sweden, the net DALY per gold ring was approximately 5 × 10−4 and 1 × 10−4 years, respectively.
A number of parameters were varied in a sensitivity analysis, such as the value perspectives in ReCiPe (individualist, hierarchist, and egalitarian), the magnitude of mercury emissions, transport distances, the amount of gold produced in the DRC (m
Au), the allocation factor of conflict DALY between minerals (a), the number of casualties in the conflict (DALYconflict,total), working environmental characterization factors (CF
WE,n
) and gold recycling. In general, although the numerical values of the results varied, the results presented above proved to be robust in terms of relative impact between the countries of origin and main contributing processes. Even if the gold is allocated a smaller share of the conflict casualties (e.g. 1 % instead of 7 %), it is still the largest contributor to the DALY of gold jewellery from the DRC.