The Condition With No Name: Autism Prevalance in a Farmworker Community

Volume 1. No. 6

The Condition With No Name: Autism Prevalance in a Farmworker Community

 

June 22, 2019

By Rebecca Álvarez, Marisol Ornelas

 

Abstract:

Background: In the United States, autism is the intellectual disability with the fastest rate of increase. Among proffered explanations for this is the possibility of environmental exposure to neurotoxins, specifically, agricultural pesticides. While several recent major studies have established a connection between pesticide exposure and increased autism prevalence rates, this research has only examined populations that had slightly higher levels of exposure than the general U.S. population. Our objective was to examine the prevalence of autism in the children of highly exposed women; i.e. farmworkers.

Method: Autism prevalence was measured among a community of P'urhépecha farmworkers living in Thermal, California. Mothers self-identified as farmworkers during pregnancy and 34 children were evaluated for autism by means of the ASSQ.

Results: Severe and previously diagnosed autism was found in 2 of 34 subjects, and one more fell on the autism spectrum as measured by the ASSQ. Most farmworker parents of autistic children were unaware that aid from the state was available to them, despite the significantly higher rates of autism in the community.

Conclusions: Significantly higher rates of autism in the children of mothers who were exposed during pregnancy to pesticides suggest this is a particularly at-risk population. Little access to state resources exists for children of farmworkers when these children are diagnosed with autism. As the rate of autism in this community is more than twice the rate in the general population, those most in need are also the most underserved by public health resources.


 

The Condition With No Name: Autism Prevalance in a Farmworker Community

By Rebecca Álvarez, Marisol Ornelas

 

The increase in autism rates

Autism has increased dramatically in the United States in recent years; while there is much scientific debate about the causes of this increase, its existence cannot reasonably be denied, even when accounting for increased reporting. Current estimates for autism prevalence in the general population range from 1 in 68 children (US Centers for Disease Control and Prevention 2014) to as high as one in 38 children (Young et al. 2011). This is a 10-fold increase in the last 40 years. It should be noted that these figures may be slightly inflated, as the Diagnostic and Statistical Manual of Mental Disorders produced by the American Psychiatric Association has recently classified autism as a spectrum disorder, and there may have been some overzealous diagnosing (Gnaulati 2013). It is now the scientific consensus that autism is determined prenatally (Polleux and Lauder 2004).

A number of theories about the root cause(s) of autism exist. Some postulate a genetic hypothesis wherein some autism results from meritocracy based on intellect, wherein highly intelligent men and women migrate to areas where industry demands their services, and thus self-select for increased risk of autism, which is correlated with high intelligence. Others find evidence for environmental factors which cause an increased risk of autism. However, it is necessary to avoid jumping to conclusions about the causes of autism, as illustrated by the now thoroughly debunked theory linking autism to vaccine use, first proposed by Andrew Wakefield (1998, retracted 2010), which resulted in unknown numbers of children contracting avoidable illnesses. Most researchers now believe that there are multiple causes of autism, and that they include both genetic and environmental factors. One of the most frequently hypothesized environmental contributors is agricultural pesticide use.

The research this paper draws upon sought to identify whether or not the children of farmworker women exposed to pesticides in the course of fieldwork during their pregnancies exhibited higher rates of autism than did the general population. Research has been conducted in the fields of toxicology, biochemistry (Nelson et al, 2001) and epidemiology (Hertz-Picciotto et al., 2006) examining the relationship between exposure to organophosphate/organochlorine pesticides and autism, with perhaps the most prominent example being a study which detailed the relationship between autism prevalence and residing in areas exposed chronically to light-to-moderate levels of pesticides in the air, or “ambient drift” (Roberts et al., 2007). This line of research recently became more complete with the publication of a large multi-year study examining the specific type of pesticide present in ambient drift and the prevalence of autism in the children of mothers exposed during pregnancy (Shelton et al., 2014). The study found that organophosphate, pyrethroid, and carbamate pesticide exposures all increased the odds ratio for autism in children of exposed mothers.

However, research is lacking which examines autism prevalence in populations of children born to heavily exposed mothers, specifically, female farmworker populations. The study which most explicitly examines the link between heavy maternal exposure via occupation and children’s intellectual disability examined mothers working in the flower industry in Ecuador (Grandjean et al., 2006). It measured the performance of these children on the Stanford-Binet copying test, and did not test for autism. This gap in knowledge is critical to fill, as an answer about the rates of prevalence in heavily exposed populations could help to further illuminate the question about the extent of the effect of pesticide exposure on autism, with significant implications for general public health as well as occupational health for female farmworkers.

The research from which this paper has its genesis took place in a farmworker community located in the Coachella Valley of California. Although technically in the city of Thermal, the community, nicknamed Duroville (in English) or Duros (in Spanish), was located on Native American reservation land administered by the Torres-Martinez Desert Cahuilla Indian and formerly belonging to Harvey Duro; hence the nickname Duros. The original inhabitants of the camp were few and almost all came from a single town, Ocomichu, in the state of Michoacan, Mexico. Throughout the 1980s and 1990s, the community expanded to include hundreds of trailers and families. In 2007, a census was taken of the community which estimated that Duros had a high-season population of 6000.

While living conditions had never been optimal, in recent years, the owner allowed the situation to deteriorate to a point where fires sometimes broke out and raged from trailer to trailer. Almost all trailers lacked electricity or air conditioning, some 800 feral dogs roamed the park, and in some places, sewage ran freely in the dirt streets. The trailer park was also located next to a waste dump, and uncovered waste frequently blew into the community when winds were high. Taken together, these conditions created a situation that the Los Angeles Times dubbed a “shantytown,” and eventually the US Government and the Bureau of Indian Affairs sued for closure of the park. The trailer park was placed into receivership by a federal judge in 2009, and a host of reporters, along with some aid groups, descended on the town. Conditions began to improve, although the waste dump still smoldered uncontained at times, and many trailers still lacked air conditioning in an environment in which temperatures regularly reached 110 degrees in the summer. These conditions were able to manifest and persist in part because the population living in Duros was among the most vulnerable in the United States: indigenous Mexican farmworkers, many undocumented, many speaking only the indigenous P'urhépecha language. Both men and women worked in the fields, with many women working up until their 8th or 9th month of pregnancy out of financial necessity. This, then, was the research setting and population we set out to study in the spring of 2012. 

Methods

The sample used in this research was obtained as randomly as possible under the circumstances; as almost all subjects could not read, advertising for participation was not possible. Subjects were recruited by contacting all residences in the community, the nature and significance of the study were explained to the subjects, and verbal informed consent was obtained. A questionnaire and research protocol were approved by the Human Research Review Board at the University of California, Riverside. The questionnaire was anonymous; no identifying information was requested, out of deference to some participants’ concerns about their legal status in the United States. The questionnaire, which was administered in Spanish and P'urhépecha, included several demographic items along with questions about the nature of exposure to pesticides during pregnancy and the number of children. The English version is as follows:

Figure 1: Pesticide Exposure and Intellectual Disability Questionnaire

Living in Trailer #_____________

Mother’s first name _____________________

Preliminary questions to ask mothers with children after identification:

1.         When did you come to the United States?        

2.         When did you come to Duroville?

3.         Did you work in the fields in Mexico? (If yes, then go to question 4, if no, then go to question 5.)

Yes [ ]               No [ ]

4.         When did you start working in the fields in Mexico?

5.         Have you worked in the fields here in the US? (if yes, then go to question 6; if no, then go to question 14.)

            Yes [ ]               No [ ]

6.         When did you start working in the fields in the US?

7.         What were some of the hardest things about that job?

8.         What type of crops did you work with?

9.         What was your job description (what did you do in the fields)?

10.       Can you describe or name what kind of pesticides were used to keep the bugs out of the fields?

11.       Did you ever inhale the pesticides or taste them in your mouth during or after working?

            If yes, can you describe this?

12.       Did you get the pesticides on your skin?

            If yes, can you describe this?

13.       Did you eat food made from the crops you picked?

            If yes, can you describe this?

14.       How many children do you have?

15.       What are their ages?

16.       Were any of them born after you started working in the fields?

Yes [ ]               No [ ]

17.       How old are you?

(Skip to ASSQ on next page, then return to items 18-21. Repeat ASSQ and items 18-21 for each child.)

18.       Has your child been diagnosed with mental retardation?                        Yes [ ]               No [ ]

19.       Does your child have physical deformities?                                            Yes [ ]               No [ ]

20.       Has your child been diagnosed with autism by a doctor?                       Yes [ ]               No [ ]

 (If yes to any of the above, ask item 21.

21.       Do you feel the help you are receiving for your child’s disability is enough?

Can you explain your answer?

While not valid as a formal medical diagnosis, the Autism Spectrum Screening Questionnaire (ASSQ) was used to determine the prevalence of autism spectrum disorders. This is a standard benchmark questionnaire used in the field of autism research (Ehlers et al., 1999), and is scored on a scale of 0-54, with a parental response cutoff score of 19 for likely incidence of autism spectrum disorder. The ASSQ is reproduced on the next page.

 

Figure 2: Autism Spectrum Screening Questionnaire

The High-Functioning Autism Spectrum Screening Questionnaire (ASSQ)

I will be reading you some statements.  Please think carefully about your child, and if any of these statements describes your child.  Please respond with “Yes,” “Somewhat,” or “No” to these statements.

Child’s first name: _____________ Born after mother started working in fields Yes [  ]   No [  ]

 

No

Somewhat

Yes

1. is old-fashioned or precocious

[  ]

[  ]

[  ]

2. is regarded as an "eccentric professor" by the other children

[  ]

[  ]

[  ]

3. lives somewhat in a world of his/her own, with restricted idiosyncratic intellectual interests

[  ]

[  ]

[  ]

4. accumulates facts on certain subjects (good rote memory), but does not really understand the meaning

[  ]

[  ]

[  ]

5. has a literal understanding of ambiguous and metaphorical language

[  ]

[  ]

[  ]

6. has a deviant style of communication with a formal, fussy, old-fashioned or"robotlike" language

[  ]

[  ]

[  ]

7. invents idiosyncratic words and expressions

[  ]

[  ]

[  ]

8. has a different voice or speech

[  ]

[  ]

[  ]

9. expresses sounds involuntarily; clears throat, grunts, smacks, cries or screams

[  ]

[  ]

[  ]

10. is surprisingly good at some things and surprisingly poor at others

[  ]

[  ]

[  ]

11. uses language freely but fails to make adjustment to fit social contexts or the needs of different listeners

[  ]

[  ]

[  ]

12. lacks empathy

[  ]

[  ]

[  ]

13. makes naive and embarrassing remarks

[  ]

[  ]

[  ]

14. has a deviant style of gaze

[  ]

[  ]

[  ]

15. wishes to be sociable but fails to make relationships with peers

[  ]

[  ]

[  ]

16. can be with other children but only on his/her terms

[  ]

[  ]

[  ]

17. lacks best friend

[  ]

[  ]

[  ]

18. lacks common sense

[  ]

[  ]

[  ]

19. is poor at games: no idea of cooperating in a team, scores "own goals"

[  ]

[  ]

[  ]

20. has clumsy, ill coordinated, ungainly, awkward movements or gestures

[  ]

[  ]

[  ]

21. has involuntary face or body movements

[  ]

[  ]

[  ]

22. has difficulties in completing simple daily activities because of compulsory repetition of certain actions or thoughts

[  ]

[  ]

[  ]

23. has special routines: insists on no change

[  ]

[  ]

[  ]

24. shows idiosyncratic attachment to objects

[  ]

[  ]

[  ]

25. is bullied by other children

[  ]

[  ]

[  ]

26. has markedly unusual facial expression

[  ]

[  ]

[  ]

27. has markedly unusual posture

[  ]

[  ]

[  ]

Results

As seen in Table 1 below, a range of ASSQ scores were reported. The finding of interest here is that 3 out of 34 children scored higher than 19 on the ASSQ, or high enough to be considered on the spectrum. The two children who scored 41 and 44 had both been formally diagnosed previously by medical professionals as having autism. 

Table 1: ASSQ Scores

Score   Frequency

0          9

1          1

2          2

3          3

4          2

5          1

6          2

7          2

8          3

9          1

11        1

13        1

14        1

16        1

17        1

20        1

41        1

44        1

Total     34

 

Though it was tempting to include the child who scored as a 20 on the ASSQ as part of the overall rate—which would result in a calculation of an autism rate in this community nearly 8 times the rate in the general population—it seems prudent to take the more conservative estimate and count only the two children who had also been previously diagnosed as having autism by medical professionals as part of the overall autism rate in the community. Even with this precaution, the rate we established in the community of Duros is 5 times the general population rate, when using the previously cited 2014 CDC prevalence rate as a benchmark.

Discussion

The striking finding that 1 in 17 children in our sample had been formally diagnosed with severe autism is counter to recent CDC findings that only 5.5 out of 1000 Latino children is diagnosed with autism. According to the US Department of Education (2004), Latino children are only half as likely as White children to be diagnosed with autism. With regard to the CDC finding for the general Latino population, this seems very likely due to underdiagnosis, a conclusion also reached by Fountain and Bearman (2011). Perhaps even more interesting is the fact that 2 of the 3 children who were identified as scoring over 19 on the ASSQ had mothers who were exposed to pesticides on a regular basis during pregnancy. This fact may have some bearing on the much higher rates of autism found in the research population. As mentioned previously, several research groups, including a team at the MIND Institute at the University of California, Davis, are investigating potential links between pesticide exposure and autism. Furthermore, as Fountain and Bearman (2011) point out, the Latino population at large is more likely to be exposed to environmental risk factors for autism.

While the rates found in this study are startlingly high, it is worth noting that these findings emerged despite the stigma over having children with autism that many P'urhépecha parents face in their community. Autism is so unheard of in the small pueblos that most Duros residents originate from that no indigenous P'urhépecha name for the condition exists; instead the Spanish word autismo is used. Parents with children who have autismo often deny the condition to friends and even sometimes family. For example, one anxious mother was encountered who denied having any children at all after being informed as to the nature of the research—this, despite both of her next-door neighbors having identified her as being the mother of a child with severe autism. Anecdotally, almost every mother in our sample had a close friend or relative who had a child with autism. It appears as though our study ran the risk of underidentifying the rate of autism in Duros due to these considerations.

Implications for public health policy and future research

Several important issues have emerged from this research, apart from the interesting finding of significantly higher autism rates in the study population. All three of the mothers who had children in the autism spectrum expressed a desire for more state resources to help their children cope with the condition, and two of the mothers stated that they were not aware that any resources existed. Of most concern to this paper is the fact that both mothers in the sample who had severely autistic children claimed to be unaware of the fact that federal and state aid was available for their children. One of the mothers was unable to work with a severely autistic 12-year old daughter unattended at home; her care consisted of locking the child in an unairconditioned trailer room while away at work in the fields—a measure taken out of desperation and necessity. Widespread lack of information or misinformation about the availability of resources was persistent; in fact, when the only local clinic that catered to the Duros community was contacted, the staff professed their lack of knowledge about autism resources. The lack of resources is not isolated to Duros; Island et al. (2012) have found that needs were unmet for the vast majority of Latina mothers of children with autism in California.

This pervasive situation, in which some of the most vulnerable members of our society are unaware of their rights, and children go untreated due to lack of access to resources, is in part the legacy of California’s Proposition 187. Passed in 1994, the measure required medical facilities and healthcare personnel to effectively act as immigration authorities by asking questions about immigration statues and reporting undocumented immigrants who sought medical help. While the proposition was overturned in 1998, the damage in the undocumented immigrant community had been done. The negative effect of Proposition 187 on immigrants’ willingness to access resources for developmentally disabled children and thus the lowered rate of diagnosis of autism is clearly demonstrated by Fountain and Bearman (2011). Many of the residents of Duros, especially adult women, are undocumented immigrants. During the course of research, again and again the subject of undocumented status was brought up by subjects, cited as a reason for everything from neighbors’ non-participation in the research study to lack of access to local resources for autistic children. The mothers of both severely autistic children expressed surprise when told about the state resources available for their children, and more surprise when told that parental immigration status was not a factor in the decision for aid.

The resources that are available to children with autism in California include Social Security income benefits, Home and Community-Based Services (HCBS) Waivers, and Medi-Cal Waivers. Although many feel that these resources are not sufficient (Island et al., 2012), they do provide some relief from the stresses that come with parenting an autistic child. Since resources for children with autism in California do exist, but parents in Duros are unaware of their existence, an important part of the resolution of the conditions observed during the course of this research is clearly greater publicity around the resources that are available—with a subtext to parents that resources are available to all regardless of immigration status. Such outreach would need to take into account the cultural specificity of Duros and other farmworker communities nearby—California already does a fair amount of public service outreach around autism in Spanish, but many members of the community do not speak Spanish. Outreach representatives could interact with community members at local clinics or public events to publicize how to access resources properly, since adult community members frequently do not read or write. The necessity of such an outreach program seems particularly salient in the light of the research findings presented herein, as the farmworkers of Thermal continue to struggle with the condition with no name.

 

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