Possible chemical contamination from plastic tubs

[xxianxx]

I am researching the possible effects of plastic containers releasing chemicals into water which may have an adverse effect on aquatic amphibians and a possible build up in invertebrates which will be used as a food source. It appears to be common practice to keep young larvae in food safe containers and plastic tubs, I do it myself when I am using baby brine shrimp with high volume water changes but change to cycled glass tanks when they get bigger and have reduced water changes. My main concern how ever is the use of plastic containers outside as grow on tubs for baby axolotls, they are set up with plants and have a low water change rate, is there a possibility of a chemical build up over a period of time ? Do these plastics contaminates have any ill effects ? Are there any plastics which are safer to use outside, where they will be exposed to the elements and could degrade relatively fast compared to tubs used inside ? I have read some background material but the science is beyond me and I would appreciate some advice on safe(r) plastic containers and possible dangers of using them, thanks.

 

[oceanblue]

The real baddies for leaching poisons are PVC which was usually plasticised with pthalates and Polycarbonate which can leach bisphenol-A. Both are not very common as containers now.

The most common plastics are Polypropylene, which does not contain plasticisers and PET which is used for 2L pop bottles. Both are reputed to be safe, as is polythene usually (HD PE ) for containers. The recycling labels help identify what you are dealing with. (PP = polypropylene)

PET does not seem to photodegrade ( a bottle in full sun with an alga culture for the last year is still ok) but polypropylene and polythene do if exposed to Ultraviolet. Containers with pigment in (such as black buckets) are a lot more light resistant but get a lot hotter in the sun which can be a problem in its own right.

A polypropylene tub became brittle within a few months in bright sun and some take away food containers I used as seed trays deteriorated within weeks. However a tub up against the north side of a wall is still fine after 3 years.

 

[oceanblue]

This paper documents some of the worries about plasticisers: PLOS ONE: Plastics Derived Endocrine Disruptors (BPA, DEHP and DBP) Induce Epigenetic Transgenerational Inheritance of Obesity, Reproductive Disease and Sperm Epimutations

and this is an easy read article based on it: BBC News - Chemical defects ?last generations?

 

[Lugubris]

All plastics, rubbers, foams ect.. leach chemicals to a certain extent, none of which are good news for amphibians (or you for that matter). I am currently in the process of phasing out as many plastic products involved in keeping my salamanders (and in my food consumption and preparation too) as possible. It is not something that is likely to cause sudden death or illness but it can slowly build up in body tissues causing physiological stress; lowering life span, weakening the immune system, and causing genetic damage among other problems.