Concentrated Animal Feeding Operations (CAFOs) in North Carolina: hogs farms and health of residential populations Julia Kravchenko, MD, PHD Assistant Professor, Department of Surgery, Duke University School of Medicine October 27-28, 2016 Museum Hotel, Durham, NC
Hogs farming characteristics 1982 1997 2007 2012 Hogs and pigs inventory: Duplin county, NC, was ranked 1 st in the U.S. (in 2012) for hog and pig sales with 3% of the U.S. sales (USDA Census of Agriculture, ACH12-4, June 2014). - Farms 11,390 3,582 2,836 2,217 - Pigs number 2,047,098 9,631290 9,887,421 8,901,434 Number of hogs and pigs sold: 3,907,278 36,451,580 43,241,680 34,456,613
Study title: Hog CAFOs and health of residential populations Data Sources: Individual level data on disease-specific mortality, emergency departments (ED) visits and hospitalizations in NC (NCHS data, HCUP data) 2007-2013: The State Inpatient Database (H-CUP SID data on disease-specific hospital admissions), The State Emergency Department Database (H-CUP SEDD data on emergency departments visits), State Center for Health Statistics, Vital Statistics-Death, UNC Dataverse. List of animal operations registered with the North Carolina Department of Environmental Quality (NCDEQ), Division of Water Resources (DWR). Adult smoking prevalence (the Behavioral Risk Factor Surveillance System (BRFSS), CDC). For zip code level analysis: Study Group 217 zip codes with hog farms registered with the DWR 15,885,645 person-years, Control group- 591 zip codes without hog farms registered with the DWR 50,150,652 person-years.
This is the first study of residential populations exposed to CAFOs Why residential populations? While studies of occupational exposure of swine operation workers exist, few studies investigate the health and medical effects of nearby residents. Residential populations may be more susceptible as they include vulnerable groups: children, people with chronic diseases, and elderly. Characteristics Study groupwith CAFOs Race: White 64.0% 73.6%* Black 28.7% 19.3%* American Indian 2.3% 0.8%* Age structure Control groupwithout CAFOs no significant differences SES factors: Median income $39,013 $46,455** Bachelor or higher degree 16.4% 24.1%** Availability of primary care health providers (per 100,000 residents) Uninsured % Smoking prevalence * - p<0.05; ** - p<0.001 54 76** no significant differences no significant differences Analyses were adjusted by income, education, health insurance, smoking, and availability of primary care providers.
Hogs farms in North Carolina Up to 171 CAFOs Up to 113 hogs per each resident (including children). Approximately 190, 000 people live in the areas with >40 hogs per each resident.
CAFO s manure contains a variety of potential contaminants: pathogens such as E. coli, growth hormones, antibiotics, and chemicals used as additives to the manure or to clean equipment, etc. CAFO with 800,000 hogs produce 1.6+ million tons of waste a year 1.5 times more than the annual sanitary waste produced by the population of the size of the city of Philadelphia, PA (GAO, 2008). Though sewage treatment plants would be required for human waste of this scale, no such treatment facility is required for this waste because it is from livestock.
Example #1: Health outcomes in study vs. control group: multivariate analysis adjusted by income, education, health insurance, smoking, and availability of primary care providers, pooled for 2007-2013. Disease (ICD-10 code) OR mortality OR hospital admissions OR ED visits Asthma (J45): all ages 1.27 # 1.17* 1.21* <9 years old n/s 1.19* 1.24* 10-19 years old n/s 1.12 # 1.24* Previously Tuberculosis (A15-A19): all ages 2.75* 1.46* n/s Hypertension (I10-I15): all ages 1.39* 1.14* 1.16* unrecognized health Ischemic heart disease (I20-I25): all ages n/s 1.12* 1.10* correlations Stroke (I60-I63): all ages n/s 1.02* n/s Diabetes mellitus type 2 (E11): all ages 1.18* 1.14* 1.25* Aplastic anemia (D60-D64): all ages 1.23* 1.13* n/s Nutritional anemia (D50-D53): all ages n/s 1.11* n/s Acute kidney failure (N17-N19): all ages 1.09* 1.07* 1.05 # * - significant under Bonferroni correction (p value less than 10-6 ), #- p<0.001; n/s non-significant
Aplastic anemia Among factors that can cause aplastic anemia are: Exposure to toxic chemicals: e.g., used in pesticides and insecticides, benzene (ingredient in gasoline) Medications: gold compounds used to treat rheumatoid arthritis, some antibiotics (e.g., chloramphenicol) Damage occurs to bone marrow, slowing or shutting down the production of new blood cells. People have higher risk of infections and uncontrolled bleeding. Chloramphenicol is used in veterinary to treat respiratory diseases and pneumonia. Was banned in Canada in 1985 (Gilmor, 1986. Can Med Assoc J 134:423-435). In China it was licensed in 1999 for control of infections in swine, cattle, and chicken. In pigs it had dose-independent irreversible aplastic anemia effect (Wang et al, 2012. Antimicrob Agents Chemother 56:1485-1490). Recent publications studied anti-microbialresistance (AMR) of E. coli to chloramphenicol in swine in NC and Iowa (Keelara et al, 2014. Foodborne Pathogenes and Disease 11:156-164; Zwonitzer et al., 2016. J Environ Quality 45:609-617).
Example #2. The discordance in medical care use and mortality: how we can intervene? Asthma: Living near hog CAFOs - lower rates of ED visits (-5.40%) and lower hospitalization rates (-9.20%). However, they have a higher proportion of ED visits (among all diseases that cased ED visits) (OR=1.20) and hospitalizations due to asthma (OR=1.21). Finally, people living near CAFOs have a higher asthma mortality rate (relative excess of asthma death rate +41%). Outcomes Higher proportion of asthma-related visits/outcomes among people living nearby hog CAFOs Difference in the rates of asthma outcomes (compared to control group) ED visits Hospitalizations Mortality OR=1.20** OR=1.21** OR=1.29* -5.40%** -9.20%** +41%* * p<0.001, **p<0.0001 Similar patterns of medical care use were observed for: - the whole group of cardiovascular diseases: - hypertension mortality OR=1.39, hospitalizations OR=1.14, ED OR=1.16; - IHD mortality OR=1.11, hospitalizations OR=1.22, ED OR=1.31, - stroke mortality OR=1.19, hospitalizations OR=1.09, ED OR=1.25), - acute kidney failure mortality OR=1.10, hospitalizations OR=1.14, ED OR=1.25.
Example #3. Number of hogs, number of hogs farms and health outcomes, multivariate analysis, adjusted for smoking prevalence and median household income. Glomerular diseases (incl. nephritic/nephrotic syndrome and nephropathy): from +11% more hospitalizations (per 100,000 increase in number of pigs), depending on season (highest in spring), from +13% more ED visits (per 100,000 increase in number of pigs), depending on season (highest in spring). Number of hogs was a better predictors of health outcomes among people living in nearby communities than number of hog farms. We hypothesize that the measures protecting the environment could be not sufficient in certain farms.
How to effectively protect the environment??
Points for discussion Planning of medical resources (number of hospital beds and emergency rooms) and access to medical care with specific focus of high-risk diseases. Children-oriented program for prevention, early diagnosis, and effective treatment of asthma in children living in the communities located in close proximity to hogs CAFOs. Surveys in residential communities to identify whether there are some financial, transformational/related to the distance, or behavioral/cultural factors that prevent the residents from visiting ED and hospitals. Further detailed analysis of associations of air contaminants and water quality with health outcomes in residential communities in NC areas with hogs CAFOs. Medical costs of improvements of access to medical care. To develop recommendations for health care policy in the affected areas.
Let s find the ways to co-exist and live a healthier life.
Study team: H. Kim Lyerly Julia Kravchenko Sung Han Rhew (post-doc) Pankaj Agarwal We thank Igor Akushevich (Associated Professor at SSRI, Duke University) for his help in analysis. We thanks for information and consultations on the data on hog farms operations and air quality: Amy Keyworth, Christine Lawson, Evan Kane from the NC Division of Water Resources John Walker and Jesse Bash from the U.S. EPA We thank Fred and Alice Stanback for supporting this study with a philanthropic donation.
Appendix
Cattle and calves (left) and poultry (right) industries on North Carolina, 2012 census. Source: USDA NASS, 2012 Census of Agriculture