Author s response to reviews Title: Self-reported acute pesticide intoxication in Ethiopia. Authors: Amare Nigatu (Amare.Nigatu@uib.no;Amare.Nigatu@igs.uib.no) Magne Bråtveit (Magne.Bratveit@uib.no) Bente Moen (Bente.Moen@uib.no) Version: 1 Date: 07 Mar 2016 Author s response to reviews: Authors' response to reviews Title: Self-reported acute pesticide intoxications in Ethiopia Authors: Amare Workiye Nigatu: Amare.Nigatu@uib.no Bente E Moen: Bente.Moen@uib.no Magne Bråtveit: Magne.Bratveit@uib.no Version 2, Date: 7th March 2016
Dear Editor We appreciate the feedback provided to the paper Self-reported acute pesticide intoxication in Ethiopia, and pleased that the reviewers found the study relevant and important in the field of occupational pesticide intoxication. We have gone through the comments and incorporated, where possible, the feedback from the reviewers into the paper. The changes are marked with track changes; the pages and lines numbers shown in the response letter are based on the corrected version. Best regards, Amare Workiye Reviewer #1: This paper describers the results of interviews carried out to identify reported signs or symptoms possibly related to excessive pesticide exposure. The author define as Acute Pesticide Intoxication any reported episode with two or more of a list of symptoms, according to an internationally accepted, although questionable, definition. As all interviews, there might recollection bias: however, these bias seem to be compensated across groups. In fact, the main result of this paper is that individuals working in the flower factory report more episodes of API. This is where the authors should concentrate, and in fact any increase observed in resident near the factory appear to be due to working in the factory rather than living close to the factory. This is not clearly enough discussed by the authors, which tend to overstate the effect of living near the factory. It is suggested that the emphasis on reporting the results and of the discussion be put on this fact, which certainly requires scrutiny and possibly intervention in the factory. We agree with the comment that the increased API among those living close to the flower farm was found to be due to working at the flower farm. This has been clearly stated in the text; however, to give it more emphasis we have made changes in the text (p.8-9; line 16-26 & 1-5 and p.9-11; line 7-15, 20-26 & 1-14). Additionally we have suggested further study to investigate
the possible factors in the study area and to improve pesticide handling at the flower farms (p.11-12; line 415-416 & 464-465). Reviewer #2 1. Was there any question on duration of pesticide use? We did not ask about the duration of pesticide use since our objective in the present study was to find out the prevalence of acute pesticide intoxication in the past 12 months, but we agree that knowing the duration of pesticide use might provide additional information to estimate the risk and chronic health effects of pesticide exposure. We will consider this in future studies. 2. Any question on type of pesticide used? We did not ask about the type of pesticide used as most of the participants in the study area had low levels of education. It was unlikely that they could able to mention the types of pesticides used. We have mentioned this as a limitation of the present study (p 12; line 2-3). However, in a previous study among several flower farms we asked about the type of pesticide used most in the farms, hence we made changes in the text (p. 9; 10-15). The flower farm in the present study was included in the previous study, and the results are therefore relevant. 3. Any question on frequency of API symptoms over past 12 months? Yes. Respondents were asked if they ever felt health problems within 48 hours of pesticide exposure in the last 12 months (p.17, Table 1-section 5). The results were described in the text (p.8; line 10-12). However, we did not ask for the frequency of each reported symptoms; we adopted WHOs definition of API for field surveys, which is based on a plausible description of pesticide exposure and two or more typical pesticide related symptoms.
4. Any information on participants who did not use pesticides, but had symptoms similar to API, i.e., possible "controls"? This may be important because screening criteria for API are subjective and subject to false interpretation. A comparison between subjects with symptoms with pesticide exposure vs. symptoms without pesticide exposure may be relevant. This analysis can not be performed in the present study. The reason is the way we asked the questions related to API. As explained in the methods: The respondents, who explained a plausible description of exposure to pesticides; and reported to have experienced health problems within 48 hours of the exposure once or several times the past year, were asked to state the health symptoms they had. The interviewers then ticked off the symptoms they mentioned from the list in the questionnaire. This means that persons without any exposure to pesticides were not asked about any symptoms. 5. More statistical interpretations may be useful, e.g., apart from prevalence rates, chi square tests for API symptoms vs. pesticide use; vs. farm worker status; vs. household distance from farms with Odds Ratio, i.e., estimation of risk may be useful. We agree that more statistical interpretations would be useful, hence we compared API prevalence vs. flower farm worker status (different job grioups in the flower farm). APIvs. living proximity could not be analysed in more detail than we already have done as we did not collect information on individual household distance in meters from the flower farm(p. 8-9; line 16-26 & 1-5). API vs. pesticide use can not be analysed as stated in the previouos comment. Reviewer #3: 1. The research question posed by the authors is found to be well addressed. 2. In materials and methods:
It is understood from the methodology that from each of the household, usually head of the household was selected as respondent, if head of the household was not available, who was the respondents for that particular household and what was the criteria We agree with the comment and made a change in the text to describe the method more clear (p. 4 & 7; line 14-16 & 20-21). Why a total of 11 villages out of 68 villages were selected randomly, not clear? We agree with the comment and have changed the text to make the information clearer (p.5; line 17-18). Information regarding exposure of the respondents to pesticides which caused API within 48 hours, needs elaboration. In the questionnaire, the question related to the pesticides exposure consisted of three answers. These answers are not sufficient to provide information regarding the particular exposure of the pesticides that caused API of the respondents within 48 hours.. We have made changes in the text (p.6; line 1-18) and in Table 1 (p.17; section 6) making our questioning related to the pesticide exposure more clear. However, we are not able to link exposure to specific types of pesticides to the API-symptoms. As stated earlier most of the participants in the study area had low levels of education, and it was unlikely that they could able to specify the pesticides used. We have now made additional analysis on whether the APIsymptoms were associated with pesticide exposure related to household pest control, own farm or flower farm (p.8-9; line 26-5). As mentioned earlier, the respondents, who presented a plausible description of exposure to pesticides and reported to have experienced health problems once or several times the past year, were asked to state the health symptoms they experienced. This method of obtaining the information on API might be inexact, that is true. We have mentioned this as a limitation in the discussion (p.12; line 2-4). 3. Data used in this study could not provide enough information regarding exposure to the pesticides that caused API within 48 hours
The API symptoms mentioned by the respondents needed to be linked with the exposure to particular pesticides. Because most of these symptoms might be manifested by other common illnesses suffered by the respondents. We have now added more information on the methods on the content of the interview. It is now more clearly stated in the text that the interviewed persons were asked to report only the symptoms which were linked to the exposure to the pesticides (p.6; line 1-18). The questions are all shown in Table 1. (p. 17). However, as commented in the previous point we are not able to link exposure to specific types of pesticides to the API-symptoms. How could the respondents ascertain Bradycardia and Miosis? As mentioned in the text the respondents were asked to mention the health symptoms or to describe the health conditions they had experienced, then the interviewers ticked off the symptoms reported in a predefined list in the interview guide (see table 1 in the article). Since all the interviewers were health workers, they were able to interpret the respondents descriptions of symptoms and put them in the list. This has also been mentioned in the text as a possible limitation (p.11-12; line 26-2). 4. Discussion is balanced and supported by the data? * Needs editing to make it more readers friendly We agree and we have restructured the text and tried to make it easier to read.(p. 9-12; line 7-26, 20-24, 2-14, 18-19, 24-26 & 1-5). The texts within the lines 239-250 is not clear, should be re-written. 'Poor working conditions, inappropriate handling and storage of pesticides, lack of safety training.' are the findings of the current study, if not then give proper reference? The mentioned references (14,22) did not provide sufficient information to support it.
We agree with the comments given and have changed this text. (p.10-11; line 20-24 & 3-7). 5. Conclusion : As the researchers are not sure about the exposure to pesticides, the statement in the conclusion 'the prevalence of API among the population in the study area was 26%' (line- 279-280) may be replaced with 'the prevalence of symptoms attributable to API ' or with other better words. We have adjusted the conclusion written at the end of the discussion and in the abstract to be the same, and to answer the objectives of the study better.. (p. 2 & 12; line 23-26 & 11-14). 7. Limitation: as a limitation of this study, researchers mentioned about the re-call bias during the interview regarding API symptoms. To reduce re-call bias the researcher should ask some more questions related to exposure and occurrence of API symptoms. We agree that our interview could have been better with more questions about the exposure to pesticides and the API symptoms. We will remember this for future studies. 8. The authors acknowledged their work properly 9. Abstract seems to be adequately summerised the article and able to convey the findings 10. In Result section Table 1- is it a interview guide or questionnaire? It was an interview guide Why did the researchers asked the respondents same question twice in different variable?
We had made a misprint in the article table 1 and omitted the repition (p.17; Table1, section 5). 11. The writing of this manuscript needs proper editing to make it more readers friendly.. We agree and have made changes throughout the text to make it readers friendly.