Determination of chlorotriazines, methylthiotriazines and one methoxytriazine by SPE-LC-UV in water samples.

Triazine herbicides form a wide group of substances that belong among the most common agrochemicals applied for pre- and post-emergence weed control. So, they can be found in the environment at trace level. In order to determine their concentrations in water samples by the usual analytical techniques, a preconcentration step is commonly necessary. In this paper, a simple analytical method for the quantification of eight triazines (three chlorotriazines, four methylthiotriazines and one methoxytriazine) in water samples by solid phase extraction-reversed phase liquid chromatography (LC) has been developed. LC shows good analytical performance for simultaneous multiple triazine analysis (repeatability <2%, reproducibility <3%), except for prometon (repeatability 5.52%, reproducibility 16%). The results, obtained by using carbograph and polymeric sorbents for solid phase extraction (SPE), have been compared. The limits of quantification achieved permit the application of the proposed SPE-LC method for the determination of eight triazines in water samples (0.0065-0.028 mug l(-1)).

[Association of air pollution caused by sulphur dioxide and total number of particles in suspension and daily mortality in the city of Madrid (1986-1992)]. / Asociación entre la contaminación atmosférica por dióxido de azufre y partículas totales en suspensión y la mortalidad diaria en la ciudad de Madrid (1986-1992).

OBJECTIVE: The aim of the study is to quantify the relationship between sulphur dioxide (SO2), total suspended particulate (TSP) and daily mortality in Madrid. METHODS: Data were plotted to exhibit the functional relationship between SO2, TSO and mortality. Box-Jenkins prewhitening method was used to detect lags and weights from the transfer function. Multivariate ARIMA models were built to control for confounding variables (air temperature and influenza epidemics). RESULTS: Graphic analysis suggested a logarithmic relationship between SO2 and mortality, and lineal relationship with TSP. No evidence of a threshold was found for each pollutant. Cross-correlation functions showed a statistically significant relationship between daily mortality caused by organic, cardiovascular and respiratory diseases and air pollution. The first lag was statistically significant for TSP and the third lag for SO2. Multivariate models gave a coefficient beta = 0.039 for TSP and beta = 1.04 for SO2 indicating a 6.6% increase in mortality for each 100 micrograms/m3 increase in TSP and a 2.2% for SO2. CONCLUSIONS: The result suggest a causal relationship between daily mortality and air pollution in Madrid.

Air pollution and mortality in Madrid, Spain: a time-series analysis.

OBJECTIVE: To assess the relationship, if any, between air pollutant (sulfur dioxide and total suspended particulate) levels and mortality in the city of Madrid during the period 1986-1992, controlling for weather, season, and influenza epidemics. METHODS: Daily death counts were obtained from the Regional Mortality Registry. Pollution data were supplied by the Municipal Monitoring Network. Time-series analysis methodology was used to assess the link between non-accidental as well as circulatory- and respiratory-disease mortality, on the one hand, and mean daily concentrations of SO2 and total suspended particulate (TSP), on the other. Multivariate autoregressive integrated moving-average (ARIMA) models were used to adjust for season, temperature, relative humidity, and influenza. A sensitivity analysis was run to assess the robustness of the estimators. RESULTS: Graphical analysis revealed a linear relationship between mortality and TSP. The relationship was logarithmic in the case of SO2. TSP lagged 1 day and SO2 lagged 3 days with an independent effect on mortality. This relationship was produced without the detection of a minimal threshold in emission values. CONCLUSIONS: These results support the hypothesis of an association between pollution levels and mortality between 1986-1992 in Madrid. Additional measures designed to reduce pollution levels without compromising thermal comfort should be implemented.

[The effect of atmospheric variables on mortality due to respiratory and cardiovascular diseases in those over 65 in the Community of Madrid]. / Influencia de variables atmosféricas sobre la mortalidad por enfermedades respiratorias y cardiovasculares en los mayores de 65 años de la Comunidad de Madrid.

OBJECTIVE: To investigate the influence of environmental variables on daily mortality, due to respiratory and cardiovascular diseases, in the C.M. from 1986 to 1991. METHODOLOGY: The environmental and mortality variables are correlated between cold and heat effects, checking the possible coincidence of models between temperature and mortality by Box-Jenkins models. The filtered mortality is correlated to the daily average temperatures, for 0-15 lags. RESULTS: The minimum daily mortality is produced in an average temperature of 23.9 degrees. There exists a correlation (p < 0.001) between cold temperature and all the mortality causes in the 15 analysed lags. A correlation (p < 0.01) to vascular diseases appears with hot temperature and, among them, with cerebrovascular accidents (ACVA) in women for 0-3 lags. CONCLUSIONS: Cold temperatures increase the mortality for all the analysed lags and causes. The heat produces immediate effects on the mortality by ACVA in women.

[Daily mortality in the Madrid community during 1986-1991 for the group between 45 and 64 year of age: its relationship to air temperature]. / Mortalidad diaria en la Comunidad de Madrid durante el período 1986-1991 para el grupo de edad de 45 a 64 años: su relación con la temperatura del aire.

BACKGROUND: There are many types of work which relate mortality with different environmental factors. These focus on the general population or in the over-65 age-group, but are relatively few in those with reference to the 45-64 age group in which mortality has a large economic and social impact. The object of the present article is to analyse the existant association between daily mortality, from both diverse specific causes, as well as the air temperature in this group in Madrid. Madrid's extreme climatic characteristics make this work of special interest. METHODS: The ARIMA model was used according to the Box-Jenkins methodology for the infiltration of the daily series of mortality regarding temperature. Amongst the residuals, interrelated functions were established which establish an association between series eliminating communal seasonal factors as well as determining the length of disequilibrium between thermal extremes and excesses in mortality. RESULTS: There is a V-shaped relationship between total daily mortality and temperature. The minimum mortality rate is established at a maximum daily temperature of 33 degrees C. Excess mortality is 0.8% for each degree below 33 degrees C, while that for each degree above is 3.0%. The functions of interrelated correlation indicate that this association is clear in males regarding general mortality as well as for circulatory diseases. In the case of high temperature the effect is immediate, while in lower temperatures we have to add a delay of 10-13 days. CONCLUSION: There is a significant statistical association between mortality and temperature extremes in people of this age group. Lost life expectancy indicates the extent of the problem and the need to implement preventative measures.