So here are some scientific citations looking at the migration of antioxidants from plastics (including PVC) into food oils and fat simulants (cheese does have fat, right?).
Begley, 1997, attached
During the 1970s K. Figge (Figge 1972, 1980) studied the migration of antioxidants from HDPE, PVC and
PS into food oils and fat simulants. These studies showed that the migration to the oils and fat simulants was predictable. The migration of the antioxidant butylated hydroxy toluene (BHT) and two hydrocarbons (Ci8H38 and C23H66) from polyolefins (LDPE, HDPE, PP, and polyethylene with 5% and 13% vinyl acetate copolymer (EVA)) into heptane, water, ethanol/water solutions, «-octanol, rc-octadecane, corn oil, HB307, tributyrin, and trioctanoin at temperatures from 24 to 60°C was studied (Chang et al. 1982). They concluded from these
studies that migration of antioxidants is predictable. The amount of migration is controlled by diffusion
through the polymer according to Fick's 2nd Law and diffusion follows Arrhenius type behaviour. In
another extensive study (A. D. Little 1983) the migration of BHT, Irganox 1010, styrene, an organo-tin stabilizer and the plasticizer dioctyl adipate were measured from HDPE, LDPE, PS, impact PS, PVC and EVA into many food simulating liquids and foods. From this study it can be concluded that migration is predictable and the amount migrating to food will always be less than to the food simulant, especially food oil.
attached -- Ducruet et al, 2007 SORPTION OF AROMA COMPOUNDS IN PET AND PVC
DURING THE STORAGE OF A STRAWBERRY SYRUP
Vinyl chloride in water (attached): Vinyl chloride is primarily of concern as a potential contaminant from some grades of PVC pipe and is best controlled by specification of material quality.
I. Steinera, L. Scharfa, F. Fialab & J. Washüttla . Volume 15, Issue 7, 1998, pages 812-817. Migration of di‐(2‐ethylhexyl) phthalate from PVC child articles into saliva and saliva simulant.
Fantoni L., Simoneau C. (2003) European survey on the contamination of homogenised baby food by epoxidised soybean oil from plasticised PVC gaskets. Food Additives and Contaminants: Part A: Chemistry, Analysis, Control, Exposure & Risk Assessment 20(11) 1087-1096
Z. G. Tsvetanova and E. J. Hoekstra. 2012. Assessment of microbial growth potential of PVC flexible tubing in contact with drinking water. Water Science & Technology: Water Supply Vol 12 No 4 pp 489–495
Simoneau C., Hannaert P. (authors), Sarigiannis D. (editor) (2009) Effect of the Nature and Concentration of Phthalates on Their Migration from PVC Materials Under Dynamic Simulated Conditions of Mouthing. Publication Office of the European Union, Luxembourg, JRC Scientific and Technical Report, EUR 23813 EN. This is about toyshttp://www.foodsmart.govt.nz/whats-in-our-food/chemicals-nutrients-additives-toxins/plastic-packaging/
Polyvinyl chloride (PVC) is heavy, stiff and transparent and often used with added plasticisers such as phthalates or adipates. Common uses of PVC with plasticisers include commercial-grade cling films for over-wrap of trays in supermarkets and filled rolls at delicatessens.
From commercial cling films made from PVC – DEHA: diethylhexyl adipate is a food-compatible phthalate plasticiser and tiny amounts may migrate into fatty food (such as meat or cheese), especially with heating. DEHP (diethylhexyl phthalate) is another plasticiser that has been of concern because it can migrate, and for that reason it is not used in food-related products in USA. It has been used as jar or bottle seals and lid inserts of bottles, spreads and juices and may be in printing ink for labels.
I, too, thought that PVC was safe for cheese molds since it is used for water intake into residences and businesses. Glad I don't use that!