Table 3.

Spearman rho correlation coefficient and p-values for ex vivo lymphocyte proliferation, lysozyme activity, and corticosterone versus total blood Hg concentration.

Assay (mitogen)	Mean ± SE	No.	Year	Incubation (hr)	ρ	p-Value
T cell (Con A)	3.02 ± 0.08	13	2001	120	–0.15	0.649
T cell (Con A)	8.08 ± 2.56	10	2001	96	–0.07	0.865
B cell (LPS)	1.87 ± 0.32	12	2001	120	–0.27	0.391
B cell (LPS)	8.13 ± 10.24	9	2001	96	–0.03	0.932
B cell (PDB)a	4.28 ± 0.95	12	2001	120	–0.69	0.014
B cell (PDB)	2.82 ± 1.08	9	2001	96	–0.38	0.309
Lysozyme activitya,b	4.96 ± 0.60	12	2001	—	0.63	0.029
T cell (Con A)	36.24 ± 18.67	57	2003	120	–0.22	0.105
T cell (PHA)	115.70 ± 25.63	57	2003	120	–0.03	0.829
B cell (LPS)	2.17 ± 0.85	58	2003	96	0.06	0.642
B cell (PDB)	2.17 ± 0.55	58	2003	96	–0.08	0.544
B cell (PDB)a,c	0.66 ± 0.13	9	2003	120	–0.80	0.001
Lysozyme activity	11.02 ± 0.82	58	2003	—	0.12	0.388
Corticosterone	2.61 ± 0.39	37	2003	—	0.20	0.242

Mean values represent SI for lymphocyte proliferation, lysozyme activity (μg/μL HEL), and corticosterone (ng/mL). No health parameters varied with either straight carapace length or sex, so all size classes and sexes were pooled for statistical analyses. Mean ± SE (range) of blood Hg concentration for samples collected in 2001 (n = 13) and 2003 (n = 58) were 0.037 ± 0.013 μg/g (0.012–0.188 μg/g) and 0.029 ± 0.002 μg/g (0.006–0.077 μg/g), respectively.

^aParameters were statistically significant.

^bPearson correlation coefficient is reported for lysozyme activity versus log-transformed Hg concentration, which showed a positive correlation.

^cThese data are from the control group from the in vitro exposure; r² and p-values are reported for a linear regression, which showed a negative relationship (Figure 3).