No.

Activities

Possible exposure route

Potential receptor

Est. exposure duration and

frequency per year

Est. averaging time

for 30 yrs adult and 6 yrs child

1

Farming

i) Inhalation of contaminated dust particles during soil tilling.

ii) Ingestion of contaminated farm produce or soil ingestion by means of substance-to-hand-to-mouth (IPCS, 2005).

iii) Dermal contact through deposition of suspended particles on parts of the body.

Members of the family who provide farm labour, i.e. children and adults.

ED = 5 hrs/day, 5 days/week for 8 months (240 days) being the length of the farming season.

8 months duration of cultivation

Adults’ AT 171 days × 30 yrs = 5130 days

Children’s AT

171 days × 6 yrs = 1026 days

2

Fishing

i) Dermal contact: direct and indirect skin contact with contaminated water during fishing. Indirect contact transfers contaminants from soaked cloth to skin.

ii) Inhalation of volatile hydrocarbons from a freshly-spilled surface can be significant. Inhalation during fish smoking (a preservation technique with heat and smoke). Release trapped hydrocarbons in fish tissue into the ambient air for inhalation.

iii) Ingestion can occur by ingesting contaminated water and fish. Consumption of contaminated fish is a potential source of exposure.

Children and adults involved in fishing, fish preparation, and fish consumption.

ED = 6 hrs/day, 5 days/week for a year.

Adults’ AT = 261 × 30 = 7830

Children’s AT = 261 × 6 = 1566

3

Hunting

i) Dermal contact may occur when a hunter’s trap site becomes polluted. Direct and indirect contact via deposition of suspended hydrocarbons on skin or from cloth to skin, as he travels through different layers of polluted surfaces.

ii) Ingestion from surface-to-hand-to-mouth or ingesting contaminated wild fruits.

iii) Inhalation during movement from one trap site to another is possible since it involves travelling within and between changing layers of polluted air.

The receptors are children and adults performing this activity.

ED = 5 hrs/day, 5 days/week for a year.

Adults’ AT = 261 × 30 = 7830

Children’s AT = 260 × 6 = 1566

4

Gathering

i) Inhalation when gathering on or near a polluted site; inhalation of contaminated air or dust particles within a polluted microenvironment is possible. Also, burning of wood can release trapped hydrocarbons in plant tissue.

ii) Dermal contact can occur while walking through polluted sites or being in contact with contaminated surfaces. Suspended hydrocarbons can deposit on leaves and be transferred while walking past.

iii) Ingestion is not common in this activity except if wild contaminated fruits are consumed or surface-to-hand-to-mouth contact occurs.

Women and children are the critical receptors in this activity because they are more involved with cooking and gathering.

ED = 5 hrs/day, 5 days/week for a year.

Adults’ AT = 261 × 30 = 7830

Children’s AT = 261 × 6 = 1566