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Reef region (or many other regions).

contribution to the Healthy Reefs for Healthy People

Initiative. The study will cover a wide range of potential

contaminants and will include a food consumption

Sample Concentrations of Pesticide Residues from

survey.

Two MAR Women

Usefulness

Concentration

Times higher than ADI

Chemical

in breast milk

Contaminants in breast milk are a telling indicator

Malaoxon*

49 ppb†

49,000 times higher

of the level of contamination in the food chain and

in the environment. In general, most chemicals that

Endosulfan

2.4 ppb

12 times higher

are detrimental to marine life are also detrimental

Mirex**

9 ppb

15,000 times higher

to humans, with a variety of associated pathologies

documented in the medical and scientific literature.

DDT**

91 ppb

65 times higher

The simplicity of the argument that "many things that

Aldrin**

2.2 ppb

8 times higher

are bad for the reef are also bad for us humans" adds

to its value as an indicator. Establishing such direct

linkages has great potential for mobilizing public

†ppb = parts per billion; ADI = Allowable Daily Intake for a 2.8

kg infant. The concentration of a given contaminant (in mg/ml)

and political support for conservation and better

is multiplied by the average daily milk consumption of an infant

management of activities leading to environmental

(in ml) to produce the estimated daily intake (in mg) which is

contamination.

compared to the ADI4.

Ultimately, the usefulness of this indicator depends

* Malaoxon is a breakdown product of malathion and is ~ 10,000

on the amount of data that is collected, the strength

times more toxic.

of any correlations between contaminants in humans

** POPs (Persistent Organic Pollutants / Stockholm Convention)

and marine life, correlations between diet (particularly

seafood consumption) and human contamination, the

feasibility and costs of reliably collecting these data,

A global compilation of more than 130 records of DDT

and the degree to which public awareness campaigns

in breast milk found the highest value worldwide in rural

can lead to successful mitigation strategies.

women in Guatemala in 1971 at 76,800 micrograms

of DDT per kg of milk fat3. (One microgram per kg is

The sampling methodology is straightforward, although

sample storage, shipping and analysis are costly.

equivalent to one part per billion). In general, women

from Latin American countries demonstrated relatively

Status

Status

high DDT values due to the pesticide's continued use

in the region into the late 1990s. Now that DDT use

Consumption of fish with high concentrations has

has been banned throughout the Central American

been hypothesized to be one avenue leading to

region, concentrations are expected to decrease when

contaminant accumulation in women's breast milk.

compared to previous studies. Reductions in average

Several of the pesticide residues that Mesoamerican

milk content of 11-21% per year were seen in women

people are exposed to are known mutagens (potential

in the U.S. and Canada after the product was banned

carcinogens) and teratogens (i.e., substances that

in those countries (by 1975)3.

may cause congenital birth defects or result in

developmental abnormalities).

Data Needs

Data

One of the pesticide residues found in the MAR at

Our current information on human exposure to a

unsafe consumption concentrations is malathion, or

wide range of potential contaminants is limited, and

its more toxic breakdown product, malaoxon, which

our understanding of the risks that such chemicals

is a documented teratogen. This high exposure could

pose to infants is even more limited. The Belize

be resulting from fish consumption, residues on fruits

study should be completed by 2008. Similar studies

and vegetables, or drinking water sources, particularly

need to be conducted in other MAR countries. Diet

rainwater vats located in residential areas sprayed in

and demographic surveys need to be conducted

mosquito control programs.

to determine potential sources of exposure. Other

studies have shown that lifelong consumers of sports

Few data are available on contaminants in human

fish can have body burdens of some pesticides of two

breast milk. No comprehensive study covering a

to five times higher than the general population5.

wide range of potential agrochemical contaminants

and including a food consumption survey has been

conducted on lactating women in the Mesoamerican

SW

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