Investigating Sources of Arsenic Important to New Zealand Air Quality

This essay examines the sources of arsenic contamination in New Zealand's air, highlighting both anthropogenic and geogenic origins. Anthropogenic sources include the use of pesticides, fertilizers, herbicides, and copper chromium arsenic (CCA) in timber treatment, all of which contribute to arsenic concentration in soil, water, and subsequently, air. Historically, practices such as using arsenic-based pesticides in horticulture and cattle dips have led to significant soil contamination, which is then dispersed into the air through natural processes like wind and weathering. Timber industries using CCA treatments also contribute to arsenic contamination, especially when treated timber is used as a heating source. Geogenic sources, such as geothermal activities in areas like Taupo, also add to arsenic levels in waterways, indirectly impacting air quality. The essay underscores the complex interplay between human activities and natural processes in driving arsenic contamination in New Zealand's air.

Sources of arsenic important to New Zealand air.
High arsenic concentration in New Zealand’s ecosystem owes its origin to both anthropogenic
and geogenic sources (Robinson et al., 2006). The primary sources of innumerable arsenic-
contaminated sites in New Zealand results from human activities. The use of pesticides,
fertilizers and herbicides increases arsenic concentration. Extensive application of pesticides in
horticulture is known to increase arsenates and arsenites such as zinc, lead, magnesium, calcium
and Paris green in orchards. This leads to soil arsenic contamination (). Application of sodium
arsenite in controlling aquatic weeds is also known to add arsenic concentration in New Zealand
lakes (Huang, 2014). Large arsenic concentrations have also been recorded to result from
extensive use of arsenic pesticides in controlling ticks, lice and fleas in cattle and sheep dips.
This practice contaminated about 20000 sites in New Zealand (Robinson et al., 2006).
Historically, cattle dips have arsenic concentration of up to 2282 mg/kg occurring at up to 20-
40cm depth (Bolan and Thiagarajan, 2015). These effects are not limited to soil contamination
alone. Natural process such as wind action, air currents, weathering and other forms of dispersal
transfers these arsenic compositions to air leading air contamination.
The use of copper chromium arsenic (CCA) is another human activity that leads to arsenic
contamination in New Zealand. Consequently, majority of the areas associated with timber
industries in New Zealand or areas where timber is used are relatively more contaminated with
arsenic. Effluents from timber treatment is considered to be a major source of arsenic
contamination in both terrestrial and aquatic environments (Bolan and Thiagarajan, 2015). The
contaminated sites in this case ranges from timber dumb sites to playgrounds where timber are
used for construction. When the treated timber or coal is used as a heating sources which is
common during winter in urban areas, the emitted smock contains large concentration of arsenic.
Natural processes such as geothermal activities also contribute to arsenic contamination in New
Zealand. Geothermal areas of Taupo for instance have relatively smaller contribution to air
contamination compared water and soil contamination (Pandey and Bhatt, 2015). These
processes increase arsenic concentration of water ways that passes through these areas for
example water ways situated in North island of New Zealand