# Metal and Pesticide Assessments of Imported and Locally Cultivated Rice (_Oryza sativa_) in Senegal
## 4 Discussion  
The presence of Pb, Cd, Al, As, and B is found in all imported and cultivated rice samples from Senegal, China, Thailand, Vietnam, and South America. Based on the representative of Pb in all samples, it is noted that 81% of Pb is present on cultivated rice and the results range between 0.21 and 2.22 mg/kg (Table 1). Of the six imported kinds of rice, the Pb concentrations are above the maximum tolerated limit by WHO/FAO, 2004, which is around 0.3 mg/kg. Similarly, the Food and Drug Administration of the Department of Health has conducted several analyses of different types of rice and the obtained values were above the limit of 0.1 mg/kg. On the other hand, the Cd concentrations for rice from the six countries are lower than the value set by the Food and Drug Administration of the Department of Health, which is around 0.1 ppm. [PERSON] et al. [11], revealed the presence of Pb and Cd in rice from northern Senegal below the concentrations specified by WHO/FAO standards and the Food and Drug Administration of the Department of Health [39]. The UN-authorized amount of As in rice is 0.2 ppm. As is a natural element of the earth's crust, about 1.8 mg/kg on average [40], and is widely present in the environment, whether in the air, water, or soil. It is very toxic in its natural inorganic form and more present in rice than in the organic form [41]. However, inorganic arsenic is easily absorbed  
Figure 2: (**a**) Distribution level of Cadmium content in imported rice, (**b**) distribution level of Plomb content in imported rice, (**c**) distribution level of arsenic content in imported rice. \begin{table}
\begin{tabular}{l c c c c c c} \hline \hline
**Targeted Pesticides** & **Senegal** & **India** & **China** &
\begin{tabular}{c} **South** \\ **America** \\ \end{tabular} & **Vietnam** & **Thailand** \\ \hline Pyrethrin I & 43.85 & 25.85 & **58.38** & 33.96 & 38.31 & 37.09 \\ \hline Pyrethrin II & 1.48 & 1.09 & 1.05 & 1.43 & **1.71** & 1.19 \\ \hline Propanil & **0.73** & 0.42 & 0.37 & 0.25 & 0.32 & 0.67 \\ \hline
2,4D & 83.56 & 43.86 & **120.19** & 13.6 & 97.48 & 72.7 \\ \hline Deltamethrin & \textless{}0.01 & \textless{}0.01 & \textless{}0.01 & \textless{}0.01 & \textless{}0.01 & \textless{}0.01 \\ \hline Bensulfuron methyl & 0.65 & 0.54 & **1.05** & 0.61 & 0.67 & 0.85 \\ \hline \hline \end{tabular}
\end{table} 
Table 5: List of targeted pesticides in countries in mg/kg. by rice, according to the WHO. We note the presence of As in all imported and cultivated rice; however, rice brands from Senegal, China, South America, and Vietnam exceeded the standard set by the WHO/FAO, which is around 0.2 mg/kg. In China, the maximum tolerated limit for As is 0.15 mg/kg. As in drinking water and food can biologically accumulate at the bottom of the food chain. The main human exposure of such toxic metals, as As is from food consumption, and, upon prolonged intake of toxic elements, serious health effects may occur. With inorganic As, the most toxic fraction is known to cause skin, lung, and bladder cancer [42]. The presence of Pb and As in rice is different from one source to another [11]. Studies by [PERSON] et al. [10] showed certain amounts of Pb and Cd in local and imported rice grains sold in Shiraz, Lebanon [1]. The presence of Cd may be due to the nature of the soil, fertilizers used, and the quality of the irrigation water [3]. Several studies have suggested washing and soaking polished rice grains reduced Cd content by about 7%, indicating that Cd intake is overestimated when using Cd concentration data [43; 44]. Cd in rice was estimated in the mean range of 21 mg/kg in Japan [45]. Al is present in all rice samples at concentrations ranging between 2.22 and 95.54 mg/kg. Knowledge of the relationship between the flood recession (duration, extension, and period) and soil (moisture, texture, and depth) can be a good asset in adaptation strategies (sowing period, crop varieties). All these physical and chemical parameters can be correlated with fertilizer concentrations and periods of use.