The sources of such contaminants are uncertain, as it is difficult
to predict whether the contamination happened at the
origin of production, during processing or by adding some
ingredients that are used to enhance flavor in meat products
such as yeast or other ruminant meat or fish (Bockelmann
et al., 2008; Pollmer, 2011).
Commercially canned foods are supposed to be considered
safe because they are processed under carefully controlled conditions.
Canned meat may contain toxins if not properly processed.
Table 1 shows the mean of total viable bacterial count
to be 1912 cfu/g and Table 2 has a mean of 1290 cfu/g. These
may be considered higher than expected and it may be due to
processing practices, which might have exacerbated contamination
through poor hygienic practices. The presence of fungal
elements and bacteria (Tables 1–3) in some samples reveals the
presence of unsanitary condition in the processing plants and
their numbers were considered to be a more practical indicator
of the hygienic efficiency and microbiological status of processing
the canned products.
Our study showed that in some of the samples, the levels of
heavy metals were above the maximum permissible levels
(Table 5). The high levels of lead in most of the samples are
particularly worrying. Soldering is a source of lead contamination
in the canning process. Lead is known to induce reduced
cognitive development and intellectual performance in children
and increased blood pressure and cardiovascular disease in
adults. The toxic effects of lead, like those of mercury, have
been principally established in studies on people exposed to
lead in the course of their work. Short-term exposure to high
levels of lead can cause brain damage, paralysis (lead palsy),
anemia and gastrointestinal symptoms. Longer-term exposure
can cause damage to the kidneys, reproductive and immune
systems in addition to effects on the nervous system. The most
critical effect of low-level lead exposure is on intellectual development
in young children and, like mercury, lead crosses the
placental barrier and accumulates in the fetus. Infants and
young children are more vulnerable than adults to the toxic
effects of lead, and they also absorb lead more readily. Even
short term, low-level exposures of young children to lead are
considered to have an effect on neurobehavioral development.
Consumption of food containing lead is the major source of
exposure for the general population (Mahalakshmi et al.,
2012).
To some extent, four of our samples had Cadmium levels
above the maximum permissible limit. Cadmium may accumulate