Historical perspective of heavy metals contamination (Cd, Cr, Cu, Hg, Pb, Zn) in the Seine River basin (France) following a DPSIR approach (1950-2005).

The Driver-Pressures-State-Impact-Response approach is applied to heavy metals in the Seine River catchment (65,000 km(2); 14 million people of which 10 million are aggregated within Paris megacity; 30% of French industrial and agricultural production). The contamination pattern at river mouth is established on the particulate material at different time scales: 1930-2000 for floodplain cores, 1980-2003 for suspended particulate matter (SPM) and bed-sediments, 1994-2003 for atmospheric fallout and annual flood deposits. The Seine has been among the most contaminated catchments with maximum contents recorded at 130 mg kg(-1) for Cd, 24 for Hg, 558 for Pb, 1620 for Zn, 347 for Cu, 275 for Cr and 150 for Ni. Today, the average levels for Cd (1.8 mg kg(-1)), Hg (1.08), Pb (108), Zn (370), Cu (99), Cr (123) and Ni (31) are much lower but still in the upper 90% of the global scale distribution (Cr and Ni excepted) and well above the natural background values determined on pre-historical deposits. All metal contents have decreased at least since 1955/65, well before metal emission regulations that started in the mid 1970's and the metal monitoring in the catchment that started in the early 1980's. In the last 20 y, major criteria changes for the management of contaminated particulates (treated urban sludge, agricultural soils, dredged sediments) have occurred. In the mid 1990's, there was a complete shift in the contamination assessment scales, from sediment management and water usage criteria to the good ecological state, now required by the 2000 European Directive. When comparing excess metal outputs, associated to river SPM, to the average metal demand within the catchment from 1950 to 2000, the leakage ratios decrease exponentially from 1950 to 2000 for Cd, Cr, Cu, Pb and Zn, meanwhile, a general increase of the demand is observed: the rate of recycling and/or treatment of metals within the anthroposphere has been improved ten-fold. Hg environmental trajectory is very specific: there is a marked decontamination from 1970 to 2000, but the leakage ratio remains very high (10 to 20%) during this period. Drivers and Pressures are poorly known prior to 1985; State evolution since 1935 has been reconstructed from flood plain cores analysis; Impacts were maximum between 1950 and 1970 but remained unknown due to analytical limitation and lack of awareness. Some Responses are lagging 10 y behind monitoring and have much evolved in the past 10 y.

Long-term tolerability of benazepril in dogs with congestive heart failure.

OBJECTIVES: To test the tolerability of long-term administration of benazepril in dogs with congestive heart failure (CHF). METHODS: The study was a prospective, randomized, double-blinded, placebo-controlled clinical trial. A total of 162 dogs with New York Heart Association (NYHA) class II-IV heart failure caused by chronic valvular disease (CVD) or dilated cardiomyopathy (DCM) were enrolled. Benazepril (minimum dosage, 0.25 mg/kg) or placebo were administered orally once daily for up to 34 months. In this paper, we report results of plasma alanine aminotransferase (ALT), creatinine, potassium and urea. RESULTS: The two groups were matched at baseline (p>/=0.18). Plasma creatinine concentrations were lower during treatment with benazepril versus placebo for all dogs (p=0.14) and every sub-group tested (NYHA II, III or IV; CVD; DCM; initial creatinine >124 mumol/L), although statistical significance was not reached (p=0.14-0.6). However, significantly (p=0.035) more cases of creatinine >124 mumol/L during treatment occurred with placebo (47%) as compared to benazepril (30%). Plasma ALT and urea values did not differ between groups for all dogs (p>0.5) or any sub-group (p=0.23-1.0). Plasma potassium values did not differ between groups for all dogs (p>0.5). Although differences approached statistical significance for potassium in some sub-groups (p=0.07-0.1), there were no consistent differences between groups. CONCLUSIONS: Benazepril was well tolerated during long-term therapy in dogs with CHF and no specific precautions appear to be necessary regarding plasma ALT, creatinine, potassium or urea. The possible action of benazepril in improving renal function (evidenced via lower plasma creatinine) merits further investigation.