Toxic metals in Loggerhead sea turtles (Caretta caretta) stranded freshly dead along Sicilian coasts

Figures & data

Figure 1. Map of the recovering sites of the loggerhead turtles (Caretta caretta) stranded between 2013 and 2018 in coastal areas of Sicily, Southern Italy.

Table 1. Biometric parameters of the 40 specimens of Caretta caretta sampled.

	N	Mean ± SD	Min	Max
Weight	40	22.75 ± 11.26	10.5	52
SCL	40	51.21 ± 11.56	28	74.5
CCW	40	41.66 ± 9.83	24	59
Modified K	40	6.03 ± 3.58	2.55	18.72

Body weight (kg), SCL (straight carapace length, cm) and CCW (curved carapace width, cm) are shown.

Table 2. Microwave digestion conditions for the muscle and fat samples analysed.

Phase	Power (W)	Ramp (min)	Hold (min)	FAN
1	600	10:00	40	1
2	0	0	15	3

Table 3. As, Cd, and Pb concentrations (mg/kg w.w.) detected in the tissues of the loggerhead turtles analysed.

Element	Sample type	N	>LOD	Mean ± SD (mg/kg)	Median	min-max (mg/kg)
As	Adipose tissue	40	8 (20)	0.69 ± 1.92	1.1	<LOD-7.5
	Muscle tissue	40	13 (32,5)	0.76 ± 1.79	1.78	<LOD-9.1
Cd	Adipose tissue	40	10 (25)	0.02 ± 0.05	0.07	<LOD-0.08
	Muscle tissue	40	15 (37,5)	0.07 ± 0.24	0.02	<LOD-1.3
Pb	Adipose tissue	40	18 (45)	0.51 ± 1.29	0.29	<LOD-6.12
	Muscle tissue	40	19 (47,5)	0.65 ± 1.67	0.35	<LOD-6.9

The fourth column shows the values of the samples above the limit of detection (>LOD).

Figure 2. Boxplot, scatterplot, and correlation plot of the morphometric parameters reordered and As, Cd, Pb concentrations sorted by matrices (muscle in red and fat in blue obtained from 40 specimens). SCL = straight carapace length; CCL = curved carapace length. In the scatterplots: triangles = muscle, circle = adipose tissues. In the main diagonal the boxplot divided by group (muscle in red, fat in blue). The six-scatter plot below the principal diagonal showed a linear correlation SCL and weight, CCL and weight, SCL and CCL. The Spearman correlation coefficients between each pair of variables is above the principal diagonal. The correlation between weight and SCL is 0.805 (first row, second column) and supports the conclusion that as SCL increases, weight increase. No correlation was found between trace elements and the other parameters.