Emissions of decaBDE were calculated following the methodology described by the ECB (2002, 2004) since there is no available information about emissions of this compound in Colombia. The estimated amount of decaBDE used for EEE production in 2010 was 3.8 tonnes based on production figures and using Equation 2-1. Emissions from use in polymer applications can occur during handling of the chemical, compounding and conversion, volatilisation and waste remaining in the environment from the use of products containing the flame retardant and from disposal (Figure 2-6).
Figure 2-6 Consumption figure and losses of decaBDE from different stages of polymers in EEE/WEEE applications in Colombia.
Losses of powders during the handling of raw flame retardant can account for up to 1.6% of the handled material; this is expected to be disposed to landfill but it is possible that a small amount could reach wastewater. Compounding is thought to contribute to dust generation but in lower amounts than in the handling stage which in a worst case scenario can be around 0.06% (UCD, 1994) (0.05% to wastewater and 0.01% to air).
Polymers in EEE/WEEE Surface water: 72.3 - 108.5 kg/year
Industrial/urban soil: 217.9 - 326.8 kg/year
Kemmlein et al. (2003) studied the volatilisation behaviour of PBDEs including decaBDE.
This study found an emission rate of decaBDE of 0.28 ng/m2/hour for a TV casing which was used by ECB (2002) to calculate emission to air from this route in Europe. This emission rate was also used to calculate the emission rate in kg per year due to volatilisation of decaBDE from EEE in Colombia using a similar methodology to that in Europe (ECB, 2004, 2002): i) the total amount of polymer in EEE equipment from articles imported and in use in 2010 was estimated to be 534 tonnes (from the inventory data); ii) the amount of decaBDE in those plastics was estimated to range between 53.4 and 80.1 tonnes (the typical concentration of decaBDE in plastics is between 10 and 15%); iii) assuming a density of 800 kg/m3 and that the plastic used in finished EEE articles has a typical thickness of 2 to 5 mm, the total surface area of plastic containing decaBDE can be estimated to be between 1.34 x 105 and 3.34 x 105 m2 in 2010. Therefore, using the reported emission factor of 0.28 ng/m2/hour, the total emission of decaBDE due to volatilisation in Colombia would be between 3.28 x 10-4 and 8.19 x 10-4 kg/year.
The waste remaining in the environment refers to any particulate loss of decaBDE from the normal use of products containing the flame retardant. These particles are thought to end up mainly in industrial/urban soil but some could also be released to surface water and air. A similar approach to the one taken in a risk assessment for di-(2-ethylhexyl) phthalate (RAR, 2000) was used to estimate decaBDE losses in Europe (ECB, 2002) was used here. The approach involves several assumptions, some of them include: i) the amount of decaBDE in articles disposed each year is the same as for new articles; this would be true for the case of Colombia until the phase out of EEE products containing decaBDE in 2013; ii) only outdoor applications are considered to contribute significantly to the emissions; emission products for outdoor use are 10%; iii) the total release of decaBDE from articles over their service life is 2%; iv) emissions can also occur at disposal; v) the partitioning of emissions to soil, surface water and air is 75, 24.9 and 0.1%. Therefore, the calculation steps and the estimated waste remaining in the environment from EEE in Colombia are shown in Table 2-9.
Table 2-9 Calculation steps of waste remaining in the environment over the lifetime of products containing decaBDE in Colombia.
Calculation step Amount (kg)
Remaining decaBDE after volatilisation 53,427 Total amount in plastics for outdoor applications (10%) 5,343
Amount loss of 2% over lifetime 106.9
Total amount remaining in plastics at disposal 5,236
Emissions at disposal of 2% 104.7
Amount in EEE for disposal 5,131
Estimated amount of waste remaining in the environment 211.6 75% to industrial/urban soil
The ECB (2004) calculated emissions of decaBDE from plastic articles using data from a recycling facility of WEEE in Japan. However, in Colombia the WEEE is normally sent to landfill since recycling of these articles continues to be minimal. A similar approach to the one used previously about emissions from waste remaining in the environment was used to calculate the emissions from WEEE at disposal (Table 2-10). In this case, the calculated decaBDE in WEEE in 2010 at the inventory stage was used. Then, the amount loss during the service life of outdoor applications was removed to avoid double counting. A 2%
emission at disposal was also applied to estimate the total decaBDE loss at this stage which was then partitioned using the pattern, 75% to industrial/urban soil, 24.9% to surface water and 0.1% to air.
Table 2-10 Calculation steps of waste remaining in the environment at disposal of products containing decaBDE in Colombia.
Calculation step Amount in (kg)
Amount of decaBDE in WEEE in 2010 14,555 – 21,832 Amount from previous outdoor applications (10%) 1,455 – 2,183
Amount loss of 2% over lifetime 29.1 – 43.7
Amount loss from outdoor applications 14,526 – 21,788
Emissions at disposal of 2% 290.5 – 435.8
75% to industrial/urban soil
Textile applications in carpets
The estimated amount of decaBDE used in textiles in 2010 in Colombia would be around 7,645 to 20,387 tonnes (Section 2.4.2.1). Emissions of decaBDE from formulation and back-coating of carpets in Colombia are thought to have a similar behaviour to the UK since this process is not expected to differ significantly between countries (Figure 2-7). Therefore, for a decaBDE usage between 7,645 and 20,387 tonnes in 2010 for back-coating of carpets the estimated emissions to air and water would be 11 – 29 kg/year and 508 – 1,355 kg/year, respectively.
Leaching loss from products in use was estimated assuming that textiles subject to washing account for 2% of the total decaBDE usage and the total decaBDE loss from washing is 0.05% over the life time of the product. Therefore, a total leaching loss of 76 – 203 kg/year could be released to wastewater.
Particulate losses at disposal can be estimated following the procedure used for polymers. A 2% loss was assumed to occur from products containing decaBDE, and their releases were thought to end up in industrial/urban soil (75%), surface water (24.9%) and air (0.1%). The estimated decaBDE released to those media are 115 – 306, 38 – 102 and 0.1 – 0.3 kg/year, respectively.
Figure 2-7 Consumption figure and losses of decaBDE from different stages in textile applications in 2010 in Colombia.
Textile applications
DecaBDE consumption in Colombia: 7,675 - 20,387 ton/year
Formulation and backcoating Air: 11 - 29 kg/year Wastewater: 508 - 1,355 kg/year
Service life
Leaching loss Wastewater: 76 -203 kg/year
Disposal Air: 0.1 - 0.3 kg/year Surface water: 38 - 102 kg/year Industrial/urban soil: 115 - 306 kg/year