## 4 BPA Contamination in Canned Meat Products  
Research has shown that BPA can migrate from polycarbonate (PC) containing coatings to meat products contained in cans via two distinct routes, namely diffusion of residual BPA present in PC after the manufacture as well as hydrolysis of the coating polymer [70]. In general migration processes are also influenced by several factors such as food composition, type and duration of contact, temperature of contact, type of packaging material, nature, and amount of migrant compound [71]. Research by [PERSON] et al. revealed that cannot solid foods had 40 times higher BPA concentrations than the average BPA concentration found in canned beverages and about seven times higher than those observed in the liquid phase of the solid food canned [13]. The higher concentration of BPA in the solid foods such as meats compared liquid foods suggests the preferably migration of BPA from the coating to the solid portion of food with a higher fat content. The difference between the beverage and food could be related to the can types, coating conditions, sample matrix, presence of lipid, and sterilization differences between food and beverage cans [72]. A number of research articles have confirmed that almost 80 to 90% of BPA migration in food and beverage cans occurs during the sterilization step [73; 74; 8] which is typically performed at 121 \({}^{\circ}\)C for 90 min [73]. The latter authors also confirmed that the BPA concentration observed following the processing step did not change either following an extended period of storage (9 months) or damage to the can. Similarly, [PERSON] et al. examined the content of BPA in canned meat balls immediately after sterilization process and storing the samples at two different temperatures (20 and 40 \({}^{\circ}\)C) from 15 to 105 days. The authors observed the amount of BPA increased from 5 to 23.5 \(\upmu\)g/kg (at 20 \({}^{\circ}\)C) and from 20 to 30 \(\upmu\)g/kg (at 40 \({}^{\circ}\)C) after 15 days, further storage, however, lead to a very slow increase of BPA level [75]. Indeed, [PERSON] et al. reported no significant differences in BPA concentration in samples stored for either 40 or 70 days, although BPA levels increased following storage for 160 days at 25 \({}^{\circ}\)C [74]. [PERSON] reported that leaching BPA from epoxy resin in cans at 121 \({}^{\circ}\)C for 20 min was higher than that leached from cans held at or below 80 \({}^{\circ}\)C for 60 min [8]. Very few research studies have investigated the amount of BPA present in food stuffs with food packaging materials other than epoxy lined cans. In this regard, the experimental work of [PERSON] et al. is interesting as the authors reported lower BPA concentrations (100 times lower) in beverages and foods packaged in packaging materials such as PET, glass and TetraPak compared to epoxy-lined cans [13]. Research carried out to understand the extent of BPA contamination in canned meat and meat products in samples from different countries such as Korea, China, USA, Japan, Canada, and New Zealand have reported a concentration range of BPA from 'not detected' to 98.3 \(\upmu\)g/kg [17], <0.01-3.14 \(\upmu\)g/kg [15], <0.01-8.78 \(\upmu\)g/kg [20], 4-20 \(\upmu\)g/kg [8], 1.2-35 \(\upmu\)g/kg [76], and <20-98 \(\upmu\)g/kg [9], respectively. This variation in the observed concentrations of BPA could be related to the different compositions of the meat samples, container materials, and food processing conditions investigated. Levels of BPA reported in several canned meat products are summarized in Table 2. Lately, it has also been speculated that the substitutes for and analogues compounds of BPA such as bisphenol S (BPS), bisphenol E (BPE) and bisphenol F (BPF) can also migrate from the cans into the foods. Since few studies have addressed this issue [15; 76], more studies are needed to identify the source and concentration of these compounds in the meat and meat products.