What You Should Know About DOP/DEHP

DEHP (di-2-ethylhexyl phthalate) sometimes known as DOP (di-octyl phthalate) is a commonly used plasticizer from the phthalate ester family and has been in use in flexible PVC (Poly Vinyl Chloride) products since the 1930’s. Flexible PVC products for building, automotive, medical and packaging applications usually contain phthalates.

As phthalates have been used for such a long time, they continue to be closely studied to ensure that their use is safe. It has been known for many years that small amounts of plasticizers can leach out of the products under certain circumstances. One such circumstance is medical tubing, blood and other intravenous (IV) fluid bags where phthalate plasticizer that may have migrated into the fluid during storage can enter the patient.
In 2000, the World Health Organization’s International Agency for Research on Cancer (IARC) reclassified DEHP, the most commonly used plasticizer in flexible PVC products as non-carcinogenic to humans.

Previous to that, in 1982 they had classified these plasticizers as “possibly carcinogenic to humans”. In 1990 the European Commission established its own position that DEHP shall not be labeled or classified as a carcinogen based on studies which showed differences in how species respond to DEHP.
In reaching its 2000 decision to downgrade the classification of DEHP to “not classifiable as to carcinogenicity in humans” they reviewed more recent scientific studies that took into account the evidence that the mechanism by which DEHP induces liver tumors in rats and mice is not relevant to humans.
In 2003 the CDC released a report on phthalates that confirmed that median exposures to phthalates were well below levels that could be expected to cause health effects, based on exposure level study using blood and urine tests.

There is no evidence that anyone has been harmed by exposure to phthalate plasticizers. Nevertheless, scientific uncertainty about the potential for phthalates to disrupt the human endocrine system or reproductive development has led to significant ongoing debate about their safety. Many hospitals have pledged to reduce the use of PVC and/or DEHP.

ZDEC Acclerator for Latex Tubes

Manufacturer: Greetings!!! I came to know about you from latex consultants. I manufacture latex tubes by dipping process based in India based on dipping process.

I would like to know can I use ZDBC for curing. I use ZDEC and Sulfur for the pre-vulcanization process.  It has been said that ZDBC could give a faster curing and also possible curing in room temperature too.
            
But earlier I used once ZDBC and ZDC  for curing. But the problem I had was, when I tried to eject the tubes it cracked at certain point.  Do let me know your suggestion.
 

John Woon (Senior Latex Consultant): Yes, ZDBC is an accelerator that is active even at room temperature and therefor would give you faster curing. However, if you want to use it you have to be careful as it might lead to over curing.

The cracking you observed during stripping could be a sign of such over-curing. You need to reduce the level of ZDBC in relation to ZDEC.

If you need a comprehensive report on the technology of manufacturing of tubes by dipping process with recommended formulations, etc., I could prepare one for you for a fee.