Transcript Module 12
Module 12: Community Health • In the past few decades, there has been significant improvement in the general health of the indigenous peoples of the North • Significant disparities remain between indigenous residents and the North American populations at large • Major risks involve (1) air pollution, (2) social issues (suicides, intoxication), and (3) lifestyle related conditions (obesity, diabetes, circulatory diseases) Required Reading Health Status of Arctic Residents (Chapter 3 in AMAP Assessment 2002: Human Health in the Arctic) www.amap.no • Click on “Publications Online” on left hand menu • Scroll through publications and select folder for “AMAP Assessment 2002: Human Health in the Arctic” • Click on “Chapter 3”, which will then open in Adobe Acrobat Reader Infant Mortality: A Success Story Contrasts in Life Expectancy Contrasts in Occurrences of Low Live Births (<2500g) Contrasts in Early Mortalities Adult Mortality Patterns Cancer Incidence Rates Tuberculosis Diabetes Oral Health A Grave Social Issue: Suicide Conclusions • Mortality patterns of Indigenous peoples in the North is changing due to “Western influences” on diet and lifestyle. Cancer, strokes, and heart disease have become leading causes of death • Injury-caused mortality is disproportionate, with suicide and homicide rates markedly different compared to southern populations • Among certain Arctic peoples, obesity and type II diabetes have increased in incidence • Public health advances have increased life expectancy and decreased early mortality Module 12: Community Health cont’d Cancer in the Northwest Territories and Nunavut (A Case Study) Northwest Territories Health and Social Services. 2003. Cancer in the Northwest Territories 1990-2000, A Descriptive Report. http://www.hlthss.gov.nt.ca/content/Publications/Reports/Ca ncer/CancerintheNWT.pdf Nunavut Department of Health and Social Services. 2003. A Ten Year Profile of Cancer in Nunavut. http://www.gov.nu.ca/hsssite/Cancer_NunavutEng.pdf Cancer in the NWT - Facts • Between 1990 and 1999, an annual average of 34 cancer deaths took place in the NWT/Nunavut • Cancer diagnosis: colorectal cancer in males (22% of all diagnoses) and breast cancer in females (28%) • Lung cancer is the leading cause of cancer death (32%) • The projected cancer burden due to the aging population will present a challenge to the health care system What is Cancer? • Cancer is the uncontrolled growth of cells in the body • The immune system can normally recognize abnormal cells and destroy them • If cancer cells overcome this defense mechanism, they can multiply and form a lump or a tumor • Benign cancer: its growth remains under some control • Malignant cancer: abnormal cells invade surrounding tissue and spread to other parts of the body (via body fluids) Risk Factors • Age • Genetics • Repeated dose exposure to external substances (smoke, ultra-violet rays from the sun, environmental agents) • Acute dose exposure: radiation • Obesity • Time lag between exposure and detection means that risk factors are difficult to identify Collection of Cancer Registration Data Cancer Incidence (1992-2000) 1996 1998 1999 NWT Male Cancer Diagnoses (1992-2000) NWT Female Cancer Diagnoses (1992-2000) Prevention • • • • • • Better diagnostic approaches Quitting smoking Improvements in diet (↑fruits and vegetables) Reduced obesity Greater physical activity Control of glucose levels Module 12: Community Health cont’d Pollution and Human Health • Few health studies on effects due to exposure to environmental contaminants in the Arctic • Arctic environment has special characteristics so results of “southern” studies may not be applicable • Exposure to contaminants often involves many different substances; risks associated with individual substances are often unknown Pollution in the Arctic Key environmental characteristics: • Northward movements of air masses • Precipitation of fine particulates in the Arctic due to cold air • Thin ozone layer • Biomagnification of pollutants in food chains (e.g. POPs) • Extensive consumption of “country” food POPs in the Arctic Total DDT in maternal blood POPs in the Arctic Total PCBs in Maternal Blood POPs in the Arctic Concentration of Chlordanes in Maternal Blood POPs in the Arctic Hexachlorobenzene in Maternal Blood Benefits of Traditional Foods versus Risks from POPs • For northern communities, traditional foods are vital to cultural and physical well-being • Considering values for tolerable daily intake of POPs, most Arctic jurisdictions advise people to continue to eat traditional foods (on balance, traditional foods are best for health of Indigenous peoples) Breast Feeding versus POPs Exposure • Effects of contaminants in breast milk are poorly understood • Breast milk, especially during the first few weeks, is most important for immune system of newborns – milk intake is relatively low • Most health agencies advise that the benefits of breast feeding outweigh the risks of POPs Heavy Metal in the Arctic Mercury in Maternal Blood Source: Mostly through meat, as methyl mercury Heavy Metals in the Arctic Cadmium in Maternal Blood Key Points About Cadmium • Main Concern: • Toxic effects on the kidney (irreversible) • Main Source: • In tobacco, kidney and liver of caribou (lichen pathway) • Fetus OK: • The growing fetus is protected from cadmium because placenta accumulates the metals to be disposed at birth Radiation in the Arctic • Main Concern: • Chronic exposure to natural and anthropogenic radionuclides leads to an increased risk of cancer • Sources: • Nuclear accidents and nuclear testing • Good News: • Anthropogenic radionuclides in the Arctic are declining • Ghost of the Past: • Because of the accumulation of some radionuclides in Arctic food chains, the exposure is generally higher in the Arctic than for populations in temperate latitudes Ultraviolet Radiation in the Arctic • Depletion of ozone increases the amount of ultraviolet radiation reaching the Earth’s surface • Depletion of ozone greatest at Poles • Reflective snow cover can make the effects of ultraviolet radiation exposure especially pronounced in the Arctic Effects of Ultraviolet Radiation • Surface of the eyeball becomes inflamed up to snow blindness (especially in spring) • Sunburns • Risk of skin cancer (decreased among persons with darker skin complexion) • Aging of skin • Greater protection from clothing helps Risk Reduction Strategies of Arctic Pollution • International, regional and national risk management approaches • Regulations (to manufacture new compounds) • Monitoring • Targeted epidemiological studies Have a good summer!