Rhodes Serum Dioxin Study Information Night Wednesday 13 October - - PowerPoint PPT Presentation

Rhodes Serum Dioxin Study

Information Night Wednesday 13 October 2004

Rhodes Serum Dioxin Study

• 1. Background
• 2. Study logistics
• 3. Interpretation of study results

Background

• Dioxins
• organochlorine compounds
• produced during incomplete combustion
• natural processes eg bushfires
• chemical processes eg paper bleaching
• industrial processes eg pesticide

manufacture

Why are dioxins a problem?

• Persistent in the environment
• Accumulate in fat up the food chain
• Mass release in industrialised

countries in 1930s-60s

• Toxic

Dioxin toxicity

• Promote cancer in animal studies
• Associated with cancer (esp lung and

blood) in people

• occupationally exposed for more than 1

year

• 20 or more years latency
• Other effects in people occupationally

exposed eg skin conditions

What levels are toxic?

• International debate about possible

effects of dioxins at lower levels

• Little solid evidence to date of effects

in humans at levels most people are exposed to

• NHMRC established tolerable

monthly intake for Australians in 2002

International Body Burdens

• All populations have been exposed to

dioxins

• 95-99% of exposure

is through diet

• Fish and meat
• Eggs and dairy products

International body burdens

• Levels are falling internationally since

decreased production 20-30 years ago

• Older people have higher body

burdens

Average concentration of TCDD in human blood from general populations

1.52 2.1 2.5 2.9 3.1 3.6 4.1 4.5 5.6 7 1 2 3 4 5 6 7 8

Spain (Madrid), 1993 USA, 1995-1997 Sweden, 1990 Germany, 1994 Japan, 1991-1992 Norway, 1993 Finland, 1989-1990 Russia (St Petersburg), 1988-1989 New Zealand, 1988 USA, 1987-1988 Place and time of measurement

TCDD concentration (ng/kg fat)

• Dioxins in Australia
• National Dioxin Assessment
• Levels in Australian population lower

than other industrialised countries

• Website

www.deh.gov.au/industry/chemicals/dio xins/index.html

Australian serum dioxin levels in National Dioxin Assessment

(South East Urban, TEQ pg/g lipid)

5 10 15 20 25 30 <16 yrs 16-30 yrs 31-45 yrs 46-60 yrs >60 yrs Males Females

Dioxin levels in perspective

• Serum levels associated with cancer

and other effects in occupational cohorts

• Mean 1400-2200 pg/g
• Serum levels of Australians
• Mean 10.9 pg/g

Rhodes Serum Dioxin Study

Aim

• To follow blood dioxin levels during

remediation to:

• Identify an increase requiring review of

remediation control measures or

• To reconfirm that remediation measures

have been effective

Why?

• Dioxins on sites to be remediated
• Modelling » small levels of dioxin

containing dust

• Community concern
• Monitoring on site
• Extra level of monitoring of residents

How?

• 50 mls of blood donated from eligible

people

• Now
• at the peak of remediation
• at the end of remediation
• Blood from a control group
• Short questionnaire

50mls is 5 X 10ml tubes No other tests needed

How?

• Dioxin in serum ~ body burden
• Measurement on pooled blood

• Who is eligible to participate?
• 200 volunteers
• Men 30 and over
• Women 45 and over
• People living on the peninsula who

intend to stay living here for the next 5 years

• Not previously worked with pesticides or

at the Union Carbide site

Why these people?

• Greatest impact, if any
• Feasible
• exclude children
• Reduce variability
• eg pregnancy and breastfeeding change

body burdens

What does participation involve?

• Registration
• Completion of Consent Form and

Questionnaire

• Donation of a 50ml blood sample at

Davies Campbell de Lambert Pathology, 2 Leeds St Rhodes

What do we need?

• As many people as possible to

donate blood (at least 40)

• Precision depends on number of

people who participate

• Community input and agreement

regarding timing of second and third collections

Interpretation of results

Possible results

• Rhodes- Control: no change
• Rhodes- Control: decreased
• Rhodes- Control: increased
• by how much?
• is it significant?

Time 1 Time 2 Time 0

ACTION

Difference  8.5ng Control group Rhodes group Rhodes group Rhodes group Control group Control group Difference  8.5ng YES NO NO YES

Interpretation

• Level of detection based upon

Tolerable Monthly Intake

• Detection of a change does not mean

increased risk of health effect

• Detection of a change may mean

remediation controls not strict enough

Summary

• The Rhodes Serum Dioxin Study

aims to detect if there has been an increase in the community’s exposure to dioxin whilst remediation is being conducted on the Rhodes peninsula

NSW Health Project Team

• Dr Michael Staff
• Dr Vicky Sheppeard
• Dr Alison Rutherford
• Dr Bradley Forssman
• More information at

www.health.nsw.gov.au/rhodes

• Contact us on 9816 0234

Clinic times

• Davies Campbell de Lambert

Pathology, 2 Leeds St Rhodes

• Thursday 14 October 5pm-830pm
• Friday 15 October 10am-12pm and 3-

6pm

• Saturday 16 October 9am-1230pm