Question

Given that any level of lead exposure can have detrimental health effects, especially for children, the EPA has not established a reference dose (RED) for lead (i.e. RED=0 mg/(kg*d)). The EPA has established the action level for lead in drinking water at 15 ug/L. Calculate the average daily dose and hazard quotient for a child (body weight = 15 kg) consuming 1 L water per day containing 15 ug/L lead. If either of these values cannot be calculated, explain why and comment on what this means for health effects associated with exposure to this water. (7 points)

Answer 1

Ajantha Date Enposure doses can be calculated from ingestion of water using the equation, B=((X IR X EF) BW where, (= Contaminated Concentration (Mg/h) D = exposure dose (My 1kg/day) IR = Intake satre os contaminated water (/day) EF - Enposure factor (unitless) BW. = Body weight (kg) c=15mg/L IR = 12l day BW = 15kg EF = (F XED) AT F = Frequency of enposure (days / year) LED = Emposure claration. AT = Averrage time (EDX 365 days year) AT = 18365 = 365 F = 365 = 365 days/ EP = 1 year AT = 365 days B EF = 365 x 1 365

Enposure factor is one " Average cose b=lLXIRXEF) 15 - 15X1XI b = 10 Mg 1 kg I'day not = 1 ug 1 kg 1 day

Date Health effects Associated with enposure - to lead Contaminated water 2 It does not matter is a person breathis in, Swallows, or absorbs lead particles, the health Effects are the same, however, the body absorbs higher levels of Lead when it contain in drinking water. I wishin our bodies, lead is absorbed and stored in our bones, blood and tissue. It doesn't stay thore permenantly, rather it is stored there as a source of continual internal enposure. As we Age our bones demineralize and the internal enposcures may increse as result of larger releases. of lead from the bone tissue. There is concern. That lead may mobilize from the bone among women eindergoing menopause. post menopausal women have been found to have higher blood lead levels than premenopausal women. Health essects from short-term overenposure to lead One person can seel & Abdominal pain. & Constipated. * tired * Headachy * memory loss * Irritable

* Loss of appetite. * pain or tingling in * weak the hands and feet. Enposure to high levels of lead may ause. anemia, weakness , kidney and brain damage * Very high lead enposure can cause death * Lead can cross one placental barnier, which means pregnest women who are enposed to lead also enpose thier unboon child .. & Lead Can damage a developing baby's nervous- system ☆ Even low level lead exposure in developing babies have been found to essect behaviour and intelligence * Lead enposure can cause miscarriage, still baths and infertility * Lead Causes Neurological essects and mental setardation have also accurach to * It causes ancer in human beings... The read cool