This news item was created by students John Allan, Brent Sumner, Nathan Allen, Emily Evers, and Mike Hughes as part of their Chemistry 212 Collaborative Group Activities in WS00 under the guidance of Prof. Rainer Glaser.

Glaser's "Chemistry is in the News"
To Accompany Wade Organic Chemistry 4/e.
Chapter 20. Carboxylic Acids.
Chapter 21. Carboxylic Acid Derivatives.

For each of the following questions, please refer to the following article:

by David Poon (Hong Kong Standard, January 11, 2000)

Editorial Comments

For a family, ensuring the health and happiness of their newborn child is a primary concern. Pacifiers and other plastic play toys are great tools to calm and entertain the infant, but those benefits may be overshadowed by the dangers plastic toys could have on the child.

These plastic toys are made by polymerized PVC chains, which alone form a hard, unbendable plastic, but when a plasticiser such as phthalates (phthalate esters) are added, the PVC chains slide over each other and cause the plastic to become flexible. The plastics used in baby toys are not unique, and the introduction of phthalates into the body has also been documented by way of medical tubing and plastic containers that release the phthalates into fatty food products such as butter, cheese, and meat. PVC readily releases the phthalates as a gas and is highly soluble in blood, fat, lung, and liver tissue.

According to an article in Fundamental & Applied Toxicology the exposure of rats to phthalates over a 24 month period showed considerable increases in mortality. This Dutch Government study suggests that children ingest non-hazardous, but substantial amounts of phthalates on a daily basis, as a result of chewing and sucking on pacifiers. Children are believed to be much more susceptible to phthalates because they can't metabolize them as well. As a result of these studies and political pressure by groups such as Greenpeace , major toy retailers such as Toys R' Us have pulled products containing phthalates from their shelves. The European Union, which comprises 15 of Europe's leading economic countries, has also issued a ban on the sale of phthalate products in Europe.

Pertinent Text References
Chapter 20. Carboxylic Acids.
Chapter 21. Carboxylic Acids Derivatives (21.2a & 21-12)


Question 1: What are plasticisers? Give three products that contain them.

Answer 1: Softening agents allow plastics to become flexible therefore increasing their use in other products. Rubber boats, Action figures, Piping, etc.

Question 2: What are some possible compounds that can be substitutes to phthalates?

Answer 2: Citrate esters and other types of plastics such as latex, silicone, polyethylene, and polypropylene.

Question 3: How do plasticisers make the plastic flexible?

Answer 3: Plasticisers are worked into plastics using heat and pressure, forcing polymers and liquids (phthalates esters) together, in which state the liquids act as an internal lubricant allowing polymer chains to move about, hence making plastic flexible.

Question 4: Do a simple Fischer Esterification with propionic acid and ethanol.

Answer 4: See Wade page 930.

Question 5: Due to the overwhelming increase in price of substituting phthalates esters do you feel banning the phthalates is justified?