Draft technical document guidelines for Canadian drinking water quality - Antimony: Exposure considerations

Sources, uses and identity

Elemental antimony (Sb) is a group 15 metalloid, which has two stable isotopes (¹²¹Sb and ¹²³Sb) and 2 allotropic forms: the stable metallic form and the amorphous black form. Metallic antimony is an insoluble, silvery white, brittle crystalline solid with poor electrical and heat conductivity properties (Reimann et al., 2010; Anderson, 2012; Tylenda et al., 2015; Multani et al., 2016; Hammond and Lide, 2019).

Elemental antimony rarely occurs free in the environment but rather occurs in the form of either organic or inorganic compounds. Over 200 inorganic compounds of antimony exist in the environment, with stibnite being the most abundant, followed by the oxides of antimony and the antimonides of heavy metals, with arsenic (As - another group 15 element) being the most predominant (Andrewes and Cullen, 2003; McCallum, 2005; Reimann et al., 2010; Tylenda et al., 2015).

Antimony occurs in 4 oxidation states (-3, 0, +3 and +5) with the trivalent [Sb(III)] and the pentavalent [Sb(V)] forms being the most environmentally prevalent and toxicologically relevant species (DFG, 2007; Filella et al., 2009). The physical/chemical properties of select antimony compounds are presented in Table 1.

Table 1. Physical/chemical properties of elemental antimony and select antimony compounds. Data as reported by ATSDR (2019) and Environment and Climate Change Canada (ECCC) and Health Canada (2020)
Property	Antimony (elemental)	Antimony trioxide	Antimony pentoxide	Antimony potassium tartrate	Sodium hexahyroxy-antimonate
CAS#	7440-36-0	1309-64-4	1314-60-9	28300-74-5	33908-66-6
Molecular formula	Sb	Sb₂ O₃	Sb₂O₅	C₈H₄K₂O₁₂Sb₂∙3H₂O	NaSb(OH)6
Molecular weight (g/mol)	121.75	291.50	323.5 (anhydrous)	333.93	246.79
Water solubility (mg/L)	Insoluble	Slightly soluble	Very slightly soluble	8.3 x 10⁴(highly soluble)	594 (moderately soluble)
Vapour pressure (mm Hg)	1 at 886 °C	1 at 574 °C	N/A	N/A	N/A

N/A – not available

Environmental fate

Antimony enters the environment from natural sources (for example, windblown dust, weathering of mineral rocks - predominantly sulphides and sulphosalts, volcanic ash) and anthropogenic activities, with coal combustion, mining and smelting being the most important. Antimony is also emitted in areas of high motor vehicle traffic (for example, abrasion of tires and brake linings). Other anthropogenic sources include fire retardants, shooting ranges (in military sites), pharmaceuticals and pesticides (Andrewes and Cullen, 2003; Filella et al., 2009; Environment Canada and Health Canada, 2010; Belzile et al., 2011; Multani et al., 2016; Herath et al., 2017). Antimony may enter drinking water from plumbing solders in drinking water distribution systems (WHO, 2003).

In general, the emission of inorganic antimony compounds, more specifically antimony trioxide or diantimony trioxide (ATO; CAS RN 1309-64-4), represents the major sources of environmental antimony in industrial regions (Oorts et al., 2008; Filella et al., 2009). According to the Canadian National Pollutant Release Inventory (NPRI), in 2017, antimony compounds released to the environment totalled approximately 5.4 tonnes (NPRI, 2017).

Once in the environment, antimony undergoes redox transformations, with both the Sb(III) and the Sb(V) forms interconverting between one another and the subsequent formation of a variety of dissolved antimony species. Both Sb(III) and Sb(V) ions readily hydrolyze forming dissolved hydroxides in the Sb(III) and Sb(V) states, such as antimonite [Sb(OH)3] and the antimonate anion [Sb(OH)6- oxyanion], respectively (Oorts et al., 2008; Okkenhaug et al., 2012; Ilgen et al., 2014; Hockmann et al., 2015).

Antimony in the particulate form is mobile and easily transported in the air, favouring wet deposition (Belzile et al., 2011). Once in the soil and water, the fate of antimony is driven by precipitation and adsorption to metal oxyhydroxides. Antimony can be immobilized in soil and water by complexation with alkaline (for example, calcium and magnesium), alkali (for example, sodium and potassium), and heavy (iron and manganese being the most important) metals forming highly stable secondary minerals such as calcium antimonates. Natural/synthetic amorphous iron and manganese (oxyhydr)oxides are known for enhancing the oxidation of Sb(III) to Sb(V) (the most stable species) (Ettler et al., 2007; Oorts et al., 2008; Filella et al., 2009; Reimann et al., 2010; Okkenhaug et al., 2012; Ilgen et al., 2014; Cai et al., 2015; Hockmann et al., 2015; Herath et al., 2017). Fate studies have shown that, due to its highest sorption capacity, antimonite predominates in the soil matrix, specifically the topsoil.

Most of the dissolved antimony (pentavalent) that might be discharged to natural waters would rapidly precipitate as antimony trioxide or antimony pentoxide and be removed by sedimentation (McKee and Wolf, 1963). In natural water sources, the antimonate anion is more mobile and is the most prevalent form of antimony under aerobic conditions (ATSDR, 2019). In drinking water, the prevalence of Sb(V) can be explained by the oxidizing nature of the treatment processes generally applied (for example, chlorination or ozonation) which oxidize Sb(III) to Sb(V), and the types of plumbing solder and pipes in the distribution systems. Despite all of the above, some evidence supports that both species can coexist in the same oxygen-dependent environment as they interconvert between one another (Andrewes and Cullen, 2003; Leuz et al., 2006; Ettler et al., 2007; Oorts et al., 2008; Filella et al., 2009; Reimann et al., 2010; Belzile et al., 2011; Okkenhaug et al., 2012; Skeaff et al., 2013; Ilgen et al., 2014; Cai et al., 2015; Hockmann et al., 2015; Herath et al., 2017).

Elemental antimony is mainly used in the manufacture of alloys and certain types of semi-conductors such as infrared detectors and diodes (Multani et al., 2016; Hammond and Lide, 2019). Antimony alloys and many antimony inorganic compounds are widely used in the manufacture of lead-acid batteries, electrical equipment, anti-friction materials, flame retardants, paints, type metal in printing presses, art glass and ceramics, plastics and pottery, ammunition and fireworks, plumbing solder and pipes, transportation vehicles and lubricants (Hjortenkrans et al., 2007; Tylenda et al., 2015; Multani et al., 2016; Hammond and Lide, 2019). Antimony organic compounds are widely used as therapeutics for some parasitic diseases including visceral, mucosal, and cutaneous leishmaniasis, schistosomiasis, trypanosomiasis and ulcerative granuloma (Health Canada, 1997; DFG, 2007; Tylenda et al., 2015; Multani et al., 2016; NTP, 2018; ECCC and Health Canada, 2020). Despite its past uses, in Canada, antimony is prohibited in cosmetics and is not used as an active ingredient in pesticides (ECCC and Health Canada, 2020).

Canadian production of antimony is minimal, significantly decreasing over time from a 2013 estimate of 148 tonnes (about 0.1% of the global production) to 1 tonne in 2015, with no production anticipated after 2016 (ECCC and Health Canada, 2020). Estimated global production of the metalloid in 2020 was 153,000 tonnes, down from 162,000 tonnes in 2019, with China being the largest producer (U.S. GS, 2020).

Antimony trioxide is the most significant commercial antimony compound accounting for over 80% of global antimony use (2005 production estimate was 120,000 tonnes) (Environment Canada and Health Canada, 2010; ECCC and Health Canada, 2020). One to 10 million kg of the compound was manufactured in Canada in 2006 with importation above 1.8 million kg and average use around 3 million reported by Canadian companies the same year (Environment Canada and Health Canada, 2010). In Canada, antimony trioxide is primarily used in combination with other compounds to provide flame retardant properties. Globally, flame-retardants are expected to remain the main consumption product of antimony (U.S. GS, 2016).

Antimony compounds are not allowed as food additives in Canada. Antimony oxide is used in the manufacture of polyethylene terephthalate (PET) which is used in various food packaging applications (Environment Canada and Health Canada, 2010; CFIA, 2016; ECCC and Health Canada, 2020).

Exposure

Canadians can be exposed to antimony via food, drinking water, air and consumer products. Exposure to antimony trioxide and antimony containing substances (11 inorganic compounds) has been assessed previously (Environment Canada and Health Canada, 2010; ECCC and Health Canada, 2020). This section builds on those exposure assessments. Exposure to antimony through environmental media, food and water is expected to be low with average daily intakes of total antimony estimated at 0.019 to 0.057 µg/kg body weight (bw) per day and the highest intake (that is, 0.27 µg/kg bw per day) estimated in infants aged up to 6 months. Food (including breast milk and beverages; range 68% to 80%) and, to a lesser extent, drinking water (range 17% to 29%) have been identified as the main contributors for exposure (ECCC and Health Canada, 2020). Based on these estimated daily intakes, a source allocation factor of 30% is considered appropriate for drinking water.

Water

Water monitoring data from the provinces (municipal and non-municipal supplies), was obtained and included raw, treated and water from distribution system. Where indicated, data was separated into groundwater and surface water sources. When the source type could not be discerned, it was classified as ground &/or surface water. Samples were divided into raw, treated and distribution water and when not indicated or not possible to determine, samples were classified as R/T/D (raw/treated/distributed). Total antimony concentrations were also obtained from First Nations and Inuit Health Branch (FNIHB) (Indigenous Services Canada, 2019) and the National Drinking Water Survey (Health Canada, 2017). The exposure data provided reflect different detection limits of accredited laboratories used within and amongst the jurisdictions, as well as their respective monitoring programs. As a result, the statistical analysis of exposure data provides only a limited picture.

Overall, within all 3 datasets the detection frequency was very low, indicating that a large number of the samples had antimony concentrations below the detection limit. For this reason, the mean, median and lower percentiles were not calculated. The range of detection limits, number of detects, sample size, 90th percentile and maximum antimony concentration are presented in Table 2, for the provincial and FNIHB data, and the National Drinking Water Survey in Table 3. When the % detection is less than 10%, the 90th percentile is presented as < detection limit (DL). Ambient antimony datasets were obtained from the ECCC surface water monitoring (ECCC, 2017) and select groundwater monitoring studies supplied by some provinces (Appendix C). Overall, these datasets show that for total antimony:

Most of the maximum antimony concentrations from provincial drinking water data were low. In cases with higher maximum values, the 90th percentile is either below the detection limit or below 1.5 μg/L.
The National Drinking Water Survey of Canada had maximum antimony concentrations below 1.0 μg/L during the summer months, but had some higher concentrations in the raw and treated lake water during the winter months. There was negligible differences between raw, treated and distribution system waters.
The ECCC surface water monitoring dataset had low 90th percentiles (≤ 0.5μg/L) for each basin. One river basin, the Lower Mackenzie, had a maximum antimony concentration that exceeded 6 μg/L, however the 90th percentile for this dataset was 0.255 μg/L.
Groundwater monitoring studies, which are ambient studies and not representative of sources for drinking water, showed higher antimony levels that reflect the respective groundwater system.

Table 2. Occurrence of total antimony in Canadian drinking water
Jurisdiction (detection limit μg/L)	Municipal/non-municipal	Water type	# Detects /samples	% Detect	Total antimony (μg/L)
Jurisdiction (detection limit μg/L)	Municipal/non-municipal	Water type	# Detects /samples	% Detect	90th percentile	Maximum
Atlantic – FNIHB (0.1–1.0) [2013–2018]^{Footnote 1}	Public and semi-public	Ground - raw	2/41	4.9	< DL	0.5
		Ground - treated	0/58	0	< DL	< DL
		Ground - distribution	4/185	2.2	< DL	1.2
		Surface - raw	0/9	0	NC	< DL
		Surface - treated	0/19	0	< DL	< DL
		Surface - distribution	0/27	0	< DL	< DL
	Private wells and systems	Ground - raw	0/1	0	NC	< DL
	Private wells and systems	Ground - distribution	10/95	10.5	0.5	1.9
British Columbia^{Footnote 2} (0.1–1) [2014–2019]	Municipal	Ground - raw	87/280	31.1	1.00	15.0
		Ground - treated	2/21	9.5	< DL	0.50
		Ground - distribution	54/257	21.0	1.00	2.00
		Ground - R/T/D	99/256	38.7	0.05	1.28
		Surface - raw	10/56	17.9	0.65	3.00
		Surface - treated	2/2	100	NC	0.05
		Surface - distribution	11/30	36.7	1.00	2.00
		Surface - R/T/D	1/24	4.2	< DL	0.25
		Ground &/or surface - raw	17/39	43.6	1.00	1.46
		Ground &/or surface - treated	6/9	31.6	1.23	2.50
		Ground &/or surface - distribution	95/240	37.4	0.50	11.30
		Ground &/or surface - R/T/D	40/134	30.0	0.50	1.95
Manitoba^{Footnote 3} (0.2–2) [2009–2018]	Municipal	Ground - raw	58/775	7.5	0.20	0.99
		Ground -treated	65/1,141	5.7	< DL	1.08
		Ground -distribution	6/88	6.8	< DL	0.92
		Surface - raw	131/578	23	0.36	1.65
		Surface - treated	94/618	15	0.27	1.69
		Surface - distribution	22/74	30	0.40	0.58
		Ground &/or surface - raw	30/174	17.2	0.25	0.5
		Ground &/or surface - treated	27/205	13	0.23	0.58
		Ground &/or surface - distribution	6/29	21	0.25	0.42
Manitoba – FNIHB^{Footnote 1} (0.1–1.0) [2013–2018]	Public and semi-public	Ground - raw	26/164	15.9	0.5	1.5
		Ground - treated	19/155	12.3	0.5	0.9
		Ground - distribution	2/29	6.9	< DL	0.2
		Surface - raw	31/239	13.0	0.5	1.7
		Surface - treated	20/241	8.3	< DL	0.7
		Surface - distribution	0/4	0	NC	< DL
	Private wells and systems	Ground - raw	1/12	8.3	< DL	0.2
		Ground - distribution	0/13	0	< DL	< DL
		Surface - raw	4/7	57	NC	0.2
		Surface - treated	3/7	43	NC	0.3
New Brunswick^{Footnote 4} (0.1–2) [2013–2018]	Municipal	Ground - raw	72/1,053	6.8	< DL	6.3
		Ground - treated	5/74	6.8	< DL	0.5
		Ground -distribution	10/504	2.0	< DL	0.5
		Surface - raw	3/99	3.0	< DL	0.1
		Surface - distribution	9/298	3.0	< DL	0.2
		Ground &/or surface - raw	6/91	6.6	< DL	0.3
		Ground &/or surface - treated	25/268	9.3	< DL	4.9
		Ground &/or surface - distribution	7/188	3.7	< DL	0.3
Newfoundland^{Footnote 5} (0.5–1) [2015–2017]	Municipal	Ground - raw	0/99	0	< DL	< DL
		Ground - distribution	37/1, 216	3.0	< DL	4.5
		Surface - raw	0/627	0	< DL	< DL
		Surface - distribution	1/3,225	0.03	< DL	0.7
Nova Scotia^{Footnote 6} (1–2) [2014–2019]	Municipal	Ground - raw	0/388^{Footnote a}	0	< DL	< DL
		Ground - treated	2/388^{Footnote a}	0.5	< DL	2.6
		Surface - raw	0/400^{Footnote b}	0	< DL	< DL
		Surface - treated	1/400^{Footnote b}	0.3	< DL	5.0
Ontario^{Footnote 7} (0.08) [2014–2018]	Municipal	Ground &/or surface - raw	1,613/1,613	100	0.80	4.0
		Ground &/or surface - treated	1,305/1,305	100	0.80	1.1
		Ground &/or surface - distribution	1,367/1,367	100	0.80	2.2
Ontario – FNIHB^{Footnote 1} (0.1–0.6) [2013–2018]	Public and semi-public	Ground - raw	0/22	0	< DL	< DL
		Ground - treated	1/236	0.4	< DL	0.5
		Ground - distribution	13/111	11.7	0.3	2.3
		Surface - raw	0/60	0	< DL	< DL
		Surface - treated	2/377	0.5	< DL	0.6
		Surface - distribution	0/34	0	< DL	< DL
	Private wells and systems	Ground - raw	0/1	0	NC	< DL
		Ground - treated	0/4	0	NC	< DL
		Ground - distribution	0/53	0	< DL	< DL
		Surface - treated	0/5	0	NC	< DL
Prince Edward Island^{Footnote 8} (1.00)	Non-municipal	Groundwater- raw	0/sample size not given	0	< DL	< DL
Saskatchewan^{Footnote 9} (0.001–1) [2014–2018]	Municipal	Ground - raw	3/50	6.0	< DL	2.6
		Surface - raw	6/61	9.8	< DL	0.8
		Ground &/or surface - treated	10/50	20	0.5	0.7
		Ground &/or surface - distribution	55/607	9.0	< DL	1.1
DL – detection limit; < DL – below detection limit (for maximum with 0% detects; for 90th percentile with < 10% detects); FNIHB – First Nations and Inuit Health Branch; NC – not calculated due to insufficient sample size; R/T/D – raw/treated/distributed Footnotes Footnote 1 Indigenous Services Canada (2019) Return to footnote 1 referrer Footnote 2 British Columbia Ministry of Health (2019) Return to footnote 2 referrer Footnote 3 Manitoba Sustainable Development (2019) Return to footnote 3 referrer Footnote 4 New Brunswick Department of Environment and Local Government (2019) Return to footnote 4 referrer Footnote 5 Newfoundland and Labrador Department of Municipal Affairs and Environment (2019) Return to footnote 5 referrer Footnote 6 Nova Scotia Environment (2019) Return to footnote 6 referrer Footnote 7 Ontario Ministry of the Environment, Conservation and Parks (2019) Return to footnote 7 referrer Footnote 8 PEI Department of Communities, Land, and Environment (2019) Return to footnote 8 referrer Footnote 9 Saskatchewan Water Security Agency (2019) Return to footnote 9 referrer Footnote 10 Total groundwater samples for raw and treated Return to footnote a referrer Footnote 11 Total surface water samples for raw and treated Return to footnote b referrer

DL – detection limit; < DL – below detection limit (for maximum with 0% detects; for 90th percentile with < 10% detects); FNIHB – First Nations and Inuit Health Branch; NC – not calculated due to insufficient sample size; R/T/D – raw/treated/distributed

Table 3. Summary of total antimony concentrations from the National Drinking Water Survey (2009 to 2010)
Water type	Summer (μg/L)^{Footnote a}			Winter (μg/L)^{Footnote a}
Water type	Detects/ samples	% Detect	Max	Detects/ samples	% Detect	Max
Well – raw	1/18	5.6	0.90	1/17	5.9	0.60
Well – treated	1/17	5.9	0.50	0/16	0	< DL
Well – distribution	1/18	5.6	0.80	1/9	11.1	0.50
Lake – raw	3/21	14	0.50	4/20	20	9.40
Lake – treated	1/21	4.8	0.50	3/20	15	9.00
Lake – distribution	1/21	4.8	0.80	0/10	0	< DL
River – raw	1/26	3.8	0.80	2/22	9.1	0.80
River – treated	2/26	7.7	0.60	1/22	4.5	0.60
River – distribution	1/26	3.8	0.50	1/12	8.3	0.60
Footnotes Footnote 1 Method detection limit = 0.5 μg/L; samples were analysed using hot acid digestion; due to low % detect, 90th percentile in all cases is below the method detection limit Additionally, U.S. data was examined and a sampling campaign of 1,172 private wells in North Carolina showed antimony concentrations below 0.1 µg/L in 74.5% of first draw samples and 91.4% of 5-minute flush samples. The 90th percentiles were 0.3 µg/L and 0.1 µg/L in first draw samples and 5-minute flush samples, respectively (Pieper, 2021). Return to footnote a referrer

Food

Antimony is absorbed by the roots of vegetables and other crops grown on antimony-containing soils (WHO, 2003). Estimates of dietary exposure to total antimony for the general Canadian population were generated by Health Canada's Food Directorate, and are based on over 40,000 analytical results from 19 surveys conducted by the Canadian Food Inspection Agency (CFIA). Total antimony has been measured in a variety of food items (including cereals, dairy products, fruits and vegetables, meat and seafood, and beverages) with most (87%) of the results exhibiting levels below the limits of detection (that is, 0.0001 to 0.01 µg/g) (CFIA, 2016; ECCC and Health Canada, 2020). Similar average levels were observed (0.001 to 0.002 µg/g) for total antimony in foods and beverages in the 2016–2018 Canadian Total Diet Study (Health Canada, 2020). A level of 0.002 µg/g has been reported for total antimony in breast milk, representing an arithmetic mean of concentrations from the scientific literature in the absence of data for human milk in Canada (ECCC and Health Canada, 2020).

Dietary exposure to total antimony is expected to be low with average daily intakes of total antimony estimated at 0.013 to 0.130 µg/kg bw per day, and the highest intake (that is, 0.26 µg/kg per day) estimated in infants aged up to 6 months (95th percentile exposure 0.023 to 0.27 µg/kg bw per day). Median and 95th percentile exposure estimates to antimony for exclusively breast-fed infants under 6 months were 0.259 and 0.306 µg/kg bw per day, respectively, as determined from scientific literature in the absence of Canadian occurrence data (ECCC and Health Canada, 2020). Orange juice, milk and breakfast cereals were the main contributors to total dietary exposure for total antimony in adults aged 19 or above, accounting for approximately 16%, 12% and 9%, respectively. Total dietary exposure for total antimony in children aged 1 to 3 years was influenced by consumption of milk (26%), apple juice (19%) and orange juice (14%) among foods in the diet (ECCC and Health Canada, 2020).

Other than environmental sources, PET food packaging materials, such as trays and bottles, may also contribute to antimony in food (Filella et al., 2009) because antimony-related catalysts are used in the manufacture of PET resins. Low parts per billion levels (ppb) of total antimony were reported in water packaged in PET bottles (Shotyk et al., 2006; Westerhoff et al., 2008; Carneado et al., 2015). However, none of the packaged food (that is, domestic and imported beverages, nut and seed butters, condiments, frozen/shelf-stable heat-and-serve meals, and processed fruits and vegetable products) samples from the 2012–2014 CFIA survey had detectable levels of antimony (CFIA, 2016; ECCC and Health Canada, 2020). In Canada, the contribution of food packaging to the overall dietary exposure to antimony is considered negligible.

Consumer products

Canadians can potentially be exposed to antimony from its use (specifically ATO) in consumer products either as a polymerization catalyst, a pigment or flame retardant. The concentration of antimony compounds in consumer products generally range between 2% to 5%, depending on the type of polymer and the intended use of the finished products (Environment Canada and Health Canada, 2010; ECCC and Health Canada, 2020). Investigations have shown that children are expected to have the greatest exposure from their direct skin contact (for example, from carpets while crawling), mouthing of toys and other products, and potential inhalation of dusts containing antimony (NTP, 2018l ECCC and Health Canada, 2020).

Air

Canadians can be exposed to antimony through the air via fine particulate matter (PM2.5), which can penetrate deep into the lungs. Air antimony levels are generally higher in urban areas. Little is known about the chemical form(s) of antimony in air (ECCC and Health Canada, 2020). Rural atmospheric aerosol levels of antimony ranging from 0.04 ng/m3 in Quebec to 2.17 ng/m3 in Nova Scotia have been reported (Hopper and Barrie, 1988). Furthermore, outdoor exposure is higher than indoor exposure from household products (for example, fabrics, carpets, paints). In Windsor, Ontario, a concentration of 1.9 ng/m3 (n = 447) was estimated for the 95th percentile of antimony in PM2.5 in Canadian outdoor air (Rasmussen, 2016), increasing from a 95th of 0.7 ng/m3 (n = 910) previously reported by the National Air Pollution Surveillance in 2011. A lower 95th percentile of 0.7 ng/m3 was estimated for PM_2.5in Canadian indoor air during the same period (Rasmussen, 2016). A median level up to 8.5 mg/kg was reported in dust (95th percentile of 32 mg/kg) from a Canadian house dust study in 2010, and levels even higher, up to 63 mg/kg, were in locations close to smelters in 2016 (ECCC and Health Canada, 2020).

Soil

Environmental exposure to antimony from the soil varies as a reflection of the mineralogy of the bedrock and proximity to human sources. Total antimony levels ranging from 0 to 8 mg/kg were measured in soils from some Canadian provinces (namely, Ontario, Alberta and British Columbia) (ECCC and Health Canada, 2020).

Canadian biomonitoring data

Total antimony was measured in the urine of Canadians aged 6 to 79 years and 3 to 79 years in cycle 1 (2007 to 2009) and 2 (2009 to 2011), respectively, in the Canadian Health Measures Survey. Urinary median levels up to 0.045 µg/L (95th percentile up to 0.19 µg/L) and 0.048 µg/L (95th percentile up to 0.22 µg/L) were reported for cycle 1 and 2, respectively. In general, the measured antimony levels were slightly higher in teenagers (12 to 19 years old) and tended to be slightly higher in men as compared to women (Health Canada, 2013).

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Date modified:: 2022-12-23

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