ABSTRACT
This investigation examines the transport of metal- and pesticide-polluted dust emitted by one of the most relevant agricultural areas of Northwestern Mexico. In the contaminated area, an excessive water extraction of the aquifer and seawater intrusion caused the abandonment of fields, which are pollutant-loaded dust emitters. We used air mass forward trajectories (HYSPLIT) model to obtain particle trajectories in the wind and the use of banned pesticides as geochemical tracers for dust transported by wind. Fifty dust samples from 10 agriculture fields and 26 roof dust of a city close to the agricultural area were analyzed for their contents of zirconium, lead, arsenic, zinc, copper, iron, manganese, vanadium, and titanium, by portable X-ray fluorescence. Nine pesticides were analyzed in the roof dust and agricultural soil samples by gas chromatography. Results show that the distribution of metals was significantly different between active and abandoned fields. Arsenic-lead-copper was mainly concentrated in abandoned fields, while zinc-iron-manganese-titanium was dominant in active fields. Two potential sources of metal contamination were found by principal component analysis (PCA): (I) a mixture of traffic and agricultural sources and (II) a group related to agricultural activities. The occurrence of banned pesticides in dust deposited on roofs collected at nearby cities confirms the atmospheric transport from the agricultural area. The HYSPLIT results indicated that the dust emitted from agricultural fields can reach up to the neighboring states of Sonora, Mexico, and the USA. The impacts that these emissions can have on human health should be studied in future research.
Subject(s)
Arsenic , Pesticides , Humans , Copper , Manganese , Titanium , Arizona , Environmental Monitoring , Agriculture , Metals , Zinc , Iron , DustABSTRACT
El cáncer de cabeza y cuello comprende a todos aquellos tumores que se desarrollan en el tracto aerodigestivo superior, una de las características de éstos es su diversidad, que no es solo desde el punto de vista histológico y etiológico, sino que incluyen diversas formas de presentación, progresión y enfoques terapéuticos. Son de causa multifactorial, siendo el alcohol y el tabaco los principales factores de riesgo asociados; en los últimos años se ha relacionado a ciertos virus con potencial oncogénico con la génesis tumoral, entre ellos al Virus del Papiloma Humano, lo que ha permitido modificar el sistema de estadificación tumor primario-nodos linfáticos cancerosos-metástasis (TNM); presentándolo ahora en dos grandes grupos acorde a la Proteína supresora de tumores P16: P16+ y P16-,los cuales tienen características y manejo diferente. En vista de la heterogeneidad de la enfermedad, son diversos los tratamientos que se ha empleados para el manejo de la misma, entre ellos cirugía, radioterapia, quimioterapia e/o inmunoterapia; ésta última terapéutica, está dirigida hacia la estimulación del sistema inmune del paciente con la finalidad de generar la destrucción de las células tumorales, se realizan previo a una intervención quirúrgica para reducir el tamaño del tumor. Una forma destacable, es la del bloqueo de puntos de control inmunitarios, especialmente hacia proteínas de control inmune moduladoras de respuesta de células T, como los anti-PD-1 y los anti-CTLA-4. La inmunoterapia cada vez va tomando más protagonismo en oncología, en especial las formas de evasión de las reacciones inmunitarias por parte de las células cancerígenas(AU)
Head and neck cancer includes all those tumors that develop in the upper aerodigestive tract, one of the characteristics of these is their heterogeneity, which is not only from the histological and etiological, but also include various forms of presentation, progression and therapeutic approaches.They have a multifactorial cause, with alcohol and tobacco being the main associated risk factors, however, in recent year scertain viruses with oncogenic potential have been linked to tumor genesis, including HPV, which has made it possible tomodify the TNM staging system; now presenting it in two large groups, P16+ and P16-, which have different characteristics and management. In view of the heterogeneity of the disease, there are various treatments that have been used to manageit, including surgery, radiotherapy, chemotherapy and/ orimmunotherapy which will be determined taking into account the location and tumor extension. The latter treatment, is aimedat stimulating the patient's immune system in order to generate the destruction of tumor cells, are performed prior to a surgical intervention to reduce the size of the tumor. A remarkable therapy is that of blocking immune checkpoints, especially anti-PD-1 and anti-CTLA. Immunotherapy is becoming more and more prominent, however, there is still much to discover, so we believe that we should continue investigating the ways of evasion of immune reactions by cancer cells(AU)
