Questions:

1.    It has been stated that based on LD50 2,3,7,8 –TCDD (Tetrachlorodibenzo-p-dioxin) is the most toxic chemical known. Why might this statement misleading? How would you rephrase the statement to make more scientifically correct?

2.    Which of the following individuals is at greater risk from inhalation of an airborne contaminant: a 1-year old child, an adult female; an adult male? Explain your reasoning.

3.    Which of the following individuals is at greater risk for ingestion of a soil contaminant: an adult female?; an adult male? Explain your reasoning.

Answers:

1. The statement is misleading because the organism where the LD50 was tested was not specified. Some might think that the small amount was tested only to guinea pig (0.0006mg/kg). But it was also tested to hamster which is a thousand times more resistant than guinea pig. ‘Chemical known’ should not be used on that sentence because not all chemicals are tested its toxicity. It should be “As of now, LD50 2,3,7,8 –TCDD (Tetrachlorodibenzo-p-dioxin) is the most toxic ingested chemical according to the test that was been made to guinea pig and the hamsters which is thousand times more resistant than guinea pig.” As you can see, I also included ingestion because that was how the test was made. People should not worry with it unless they ingest it.

2. Among the three choices between 1-year old child, an adult female and an adult male, I think the 1-year old child is the most expose to a greater risk on inhaling an airborne contaminant.

*A one-year old child won’t automatically pinch their nose or shut their mouth when there is toxic substance expose. They still don’t know how to react on things around them. For example someone is burning a rubber. A child won’t resist the air that he inhale because he doesn’t know about it.

*A one-year old child would live longer than the adult. It means that when he/she reached the age of maturity while studying in Manila, he/she had already been exposed to some contaminants. And he would still live for 60 years, he still have another 50 years to inhale the cigarettes smoke from people around him. Compare to those old people who was born on the time when there are still no black smoke from the jeepneys, where cigarettes and tobacco was not that practice by lot of people, when factories was still on the blueprint and not yet starting to conquer the air with their smoke.

*A one-year old child has a weak immune system. A strong virus or a airborne contaminant could directly attack their lungs by uncontrollably inhaling it.

3. For me, adult male has the higher chance of ingesting a soil contaminant because majority of work by men is on the field or outside the office like construction workers, miners and farmers. Women are more careful instinctively on such matters like the ingestion of soil. But, if the cause of the soil ingestion are from food, no gender are exempted with it.